diff --git a/app.js b/app.js
index 9519be1..7c73f44 100644
--- a/app.js
+++ b/app.js
@@ -1,252 +1,10 @@
-'use strict';
-
-var _ = require('lodash');
-var async = require('async');
-var log = require('npmlog');
-var express = require('express');
-var querystring = require('querystring');
-var bodyParser = require('body-parser')
-
-var CopayServer = require('./lib/server');
-
-log.debug = log.verbose;
-log.level = 'debug';
-
-
-CopayServer.initialize();
-
-
-var app = express();
-app.use(function(req, res, next) {
-  res.setHeader('Access-Control-Allow-Origin', '*');
-  res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS, PUT, DELETE');
-  res.setHeader('Access-Control-Allow-Headers', 'X-Requested-With,Content-Type,Authorization');
-  next();
-});
-var allowCORS = function(req, res, next) {
-  if ('OPTIONS' == req.method) {
-    res.send(200);
-    res.end();
-    return;
-  }
-  next();
-}
-app.use(allowCORS);
-
-var POST_LIMIT = 1024 * 100 /* Max POST 100 kb */ ;
-
-app.use(bodyParser.json({
-  limit: POST_LIMIT
-}));
-
-app.use(require('morgan')('dev'));
+#!/usr/bin/env node
 
+var ExpressApp = require('./lib/expressapp');
 
 var port = process.env.COPAY_PORT || 3001;
-var router = express.Router();
-
-function returnError(err, res, req) {
-  if (err instanceof CopayServer.ClientError) {
-
-    var status = (err.code == 'NOTAUTHORIZED') ? 401 : 400;
-    log.error('Err: ' + status + ':' + req.url + ' :' + err.code + ':' + err.message);
-    res.status(status).json({
-      code: err.code,
-      error: err.message,
-    }).end();
-  } else {
-    var code, message;
-    if (_.isObject(err)) {
-      code = err.code;
-      message = err.message;
-    }
-    var m = message || err.toString();
-
-    log.error('Error: ' + req.url + ' :' + code + ':' + m);
-    res.status(code || 500).json({
-      error: m,
-    }).end();
-  }
-};
-
-function getCredentials(req) {
-  var identity = req.header('x-identity');
-  if (!identity) return;
-
-  return {
-    copayerId: identity,
-    signature: req.header('x-signature'),
-  };
-};
-
-function getServerWithAuth(req, res, cb) {
-  var credentials = getCredentials(req);
-  var auth = {
-    copayerId: credentials.copayerId,
-    message: req.method.toLowerCase() + '|' + req.url + '|' + JSON.stringify(req.body),
-    signature: credentials.signature,
-  };
-  CopayServer.getInstanceWithAuth(auth, function(err, server) {
-    if (err) return returnError(err, res, req);
-    return cb(server);
-  });
-};
-
-router.post('/v1/wallets/', function(req, res) {
-  var server = CopayServer.getInstance();
-  server.createWallet(req.body, function(err, walletId) {
-    if (err) return returnError(err, res, req);
-
-    res.json({
-      walletId: walletId,
-    });
-  });
-});
-
-router.post('/v1/wallets/:id/copayers/', function(req, res) {
-  req.body.walletId = req.params['id'];
-  var server = CopayServer.getInstance();
-  server.joinWallet(req.body, function(err, result) {
-    if (err) return returnError(err, res, req);
-
-    res.json(result);
-  });
-});
-
-router.get('/v1/wallets/', function(req, res) {
-  getServerWithAuth(req, res, function(server) {
-    var result = {};
-    async.parallel([
-
-      function(next) {
-        server.getWallet({}, function(err, wallet) {
-          if (err) return next(err);
-          result.wallet = wallet;
-          next();
-        });
-      },
-      function(next) {
-        server.getBalance({}, function(err, balance) {
-          if (err) return next(err);
-          result.balance = balance;
-          next();
-        });
-      },
-      function(next) {
-        server.getPendingTxs({}, function(err, pendingTxps) {
-          if (err) return next(err);
-          result.pendingTxps = pendingTxps;
-          next();
-        });
-      },
-    ], function(err) {
-      if (err) return returnError(err, res, req);
-      res.json(result);
-    });
-  });
-});
-
-
-router.get('/v1/txproposals/', function(req, res) {
-  getServerWithAuth(req, res, function(server) {
-    server.getPendingTxs({}, function(err, pendings) {
-      if (err) return returnError(err, res, req);
-      res.json(pendings);
-    });
-  });
-});
-
-
-router.post('/v1/txproposals/', function(req, res) {
-  getServerWithAuth(req, res, function(server) {
-    server.createTx(req.body, function(err, txp) {
-      if (err) return returnError(err, res, req);
-      res.json(txp);
-    });
-  });
-});
-
-
-router.post('/v1/addresses/', function(req, res) {
-  getServerWithAuth(req, res, function(server) {
-    server.createAddress(req.body, function(err, address) {
-      if (err) return returnError(err, res, req);
-      res.json(address);
-    });
-  });
-});
-
-router.get('/v1/addresses/', function(req, res) {
-  getServerWithAuth(req, res, function(server) {
-    server.getAddresses({}, function(err, addresses) {
-      if (err) return returnError(err, res, req);
-      res.json(addresses);
-    });
-  });
-});
-
-router.get('/v1/balance/', function(req, res) {
-  getServerWithAuth(req, res, function(server) {
-    server.getBalance({}, function(err, balance) {
-      if (err) return returnError(err, res, req);
-      res.json(balance);
-    });
-  });
-});
-
-router.post('/v1/txproposals/:id/signatures/', function(req, res) {
-  getServerWithAuth(req, res, function(server) {
-    req.body.txProposalId = req.params['id'];
-    server.signTx(req.body, function(err, txp) {
-      if (err) return returnError(err, res, req);
-      res.json(txp);
-      res.end();
-    });
-  });
-});
-
-// TODO Check HTTP verb and URL name
-router.post('/v1/txproposals/:id/broadcast/', function(req, res) {
-  getServerWithAuth(req, res, function(server) {
-    req.body.txProposalId = req.params['id'];
-    server.broadcastTx(req.body, function(err, txp) {
-      if (err) return returnError(err, res, req);
-      res.json(txp);
-      res.end();
-    });
-  });
-});
-
-router.post('/v1/txproposals/:id/rejections', function(req, res) {
-  getServerWithAuth(req, res, function(server) {
-    req.body.txProposalId = req.params['id'];
-    server.rejectTx(req.body, function(err, txp) {
-      if (err) return returnError(err, res, req);
-      res.json(txp);
-      res.end();
-    });
-  });
-});
-
-router.delete('/v1/txproposals/:id/', function(req, res) {
-  getServerWithAuth(req, res, function(server) {
-    req.body.txProposalId = req.params['id'];
-    server.removePendingTx(req.body, function(err) {
-      if (err) return returnError(err, res, req);
-      res.end();
-    });
-  });
-});
-
-// TODO: DEBUG only!
-router.get('/v1/dump', function(req, res) {
-  var server = CopayServer.getInstance();
-  server.storage._dump(function() {
-    res.end();
-  });
-});
-
-app.use('/copay/api', router);
 
+var app = ExpressApp.start();
 app.listen(port);
+
 console.log('Copay service running on port ' + port);
diff --git a/lib/client/Verifier.js b/lib/client/Verifier.js
index 2439497..639b73e 100644
--- a/lib/client/Verifier.js
+++ b/lib/client/Verifier.js
@@ -35,7 +35,8 @@ Verifier.checkCopayers = function(copayers, walletPrivKey, myXPrivKey, n) {
     }
 
     // Not signed pub keys
-    if (!WalletUtils.verifyMessage(copayer.xPubKey, copayer.xPubKeySignature, walletPubKey)) {
+    if (!copayer.xPubKey ||  !copayer.xPubKeySignature ||
+        !WalletUtils.verifyMessage(copayer.xPubKey, copayer.xPubKeySignature, walletPubKey)) {
       log.error('Invalid signatures in server response');
       error = true;
     }
@@ -53,11 +54,12 @@ Verifier.checkCopayers = function(copayers, walletPrivKey, myXPrivKey, n) {
 
 
 Verifier.checkTxProposal = function(data, txp) {
+  $.checkArgument(txp.creatorId);
+
   var creatorXPubKey = _.find(data.publicKeyRing, function(xPubKey) {
     if (WalletUtils.xPubToCopayerId(xPubKey) === txp.creatorId) return true;
   });
   if (!creatorXPubKey) return false;
-
   var creatorSigningPubKey = (new Bitcore.HDPublicKey(creatorXPubKey)).derive('m/1/0').publicKey.toString();
 
   var hash = WalletUtils.getProposalHash(txp.toAddress, txp.amount, txp.message);
diff --git a/lib/client/api.js b/lib/client/api.js
index f2224ff..3530582 100644
--- a/lib/client/api.js
+++ b/lib/client/api.js
@@ -60,8 +60,11 @@ function API(opts) {
   this.verbose = !!opts.verbose;
   this.request = request || opts.request;
   this.baseUrl = opts.baseUrl || BASE_URL;
+  this.basePath = this.baseUrl.replace(/http.?:\/\/[a-zA-Z0-9:-]*\//,'/'); 
   if (this.verbose) {
     log.level = 'debug';
+  } else {
+    log.level = 'info';
   }
 };
 
@@ -127,6 +130,8 @@ API.prototype._doRequest = function(method, url, args, data, cb) {
 
   var absUrl = this.baseUrl + url;
   var args = {
+    // relUrl: only for testing with `supertest`
+    relUrl: this.basePath + url,
     headers: {
       'x-identity': data.copayerId,
       'x-signature': reqSignature,
@@ -415,7 +420,7 @@ API.prototype.import = function(str, cb) {
 
     var xPubKey = (new Bitcore.HDPublicKey(data.xPrivKey)).toString();
 
-    data.publicKeyRing.push(xPubKey);
+    data.publicKeyRing.unshift(xPubKey);
     data.copayerId = WalletUtils.xPubToCopayerId(xPubKey);
     data.n = data.publicKeyRing.length;
     data.signingPrivKey = (new Bitcore.HDPrivateKey(data.xPrivKey)).derive('m/1/0').privateKey.toWIF();
@@ -444,6 +449,7 @@ API.prototype.getTxProposals = function(opts, cb) {
 
 API.prototype.signTxProposal = function(txp, cb) {
   var self = this;
+  $.checkArgument(txp.creatorId);
 
   this._loadAndCheck(function(err, data) {
     if (err) return cb(err);
@@ -452,7 +458,6 @@ API.prototype.signTxProposal = function(txp, cb) {
       return cb(new ServerCompromisedError('Server sent fake transaction proposal'));
     }
 
-
     //Derive proper key to sign, for each input
     var privs = [],
       derived = {};
@@ -493,6 +498,7 @@ API.prototype.signTxProposal = function(txp, cb) {
 
 API.prototype.rejectTxProposal = function(txp, reason, cb) {
   var self = this;
+  $.checkArgument(cb);
 
   this._loadAndCheck(
     function(err, data) {
diff --git a/lib/expressapp.js b/lib/expressapp.js
new file mode 100644
index 0000000..07f9de3
--- /dev/null
+++ b/lib/expressapp.js
@@ -0,0 +1,259 @@
+'use strict';
+
+var _ = require('lodash');
+var async = require('async');
+var log = require('npmlog');
+var express = require('express');
+var querystring = require('querystring');
+var bodyParser = require('body-parser')
+
+var CopayServer = require('./server');
+
+log.debug = log.verbose;
+log.level = 'debug';
+
+var ExpressApp = function() {};
+
+ExpressApp.start = function(opts) {
+  opts = opts || {};
+
+
+  CopayServer.initialize(opts.CopayServer);
+  var app = express();
+  app.use(function(req, res, next) {
+    res.setHeader('Access-Control-Allow-Origin', '*');
+    res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS, PUT, DELETE');
+    res.setHeader('Access-Control-Allow-Headers', 'X-Requested-With,Content-Type,Authorization');
+    next();
+  });
+  var allowCORS = function(req, res, next) {
+    if ('OPTIONS' == req.method) {
+      res.send(200);
+      res.end();
+      return;
+    }
+    next();
+  }
+  app.use(allowCORS);
+
+  var POST_LIMIT = 1024 * 100 /* Max POST 100 kb */ ;
+
+  app.use(bodyParser.json({
+    limit: POST_LIMIT
+  }));
+
+  app.use(require('morgan')('dev'));
+
+
+  var router = express.Router();
+
+  function returnError(err, res, req) {
+    if (err instanceof CopayServer.ClientError) {
+
+      var status = (err.code == 'NOTAUTHORIZED') ? 401 : 400;
+      log.error('Err: ' + status + ':' + req.url + ' :' + err.code + ':' + err.message);
+      res.status(status).json({
+        code: err.code,
+        error: err.message,
+      }).end();
+    } else {
+      var code, message;
+      if (_.isObject(err)) {
+        code = err.code;
+        message = err.message;
+      }
+      var m = message || err.toString();
+
+      log.error('Error: ' + req.url + ' :' + code + ':' + m);
+      res.status(code || 500).json({
+        error: m,
+      }).end();
+    }
+  };
+
+  function getCredentials(req) {
+    var identity = req.header('x-identity');
+    if (!identity) return;
+
+    return {
+      copayerId: identity,
+      signature: req.header('x-signature'),
+    };
+  };
+
+  function getServerWithAuth(req, res, cb) {
+    var credentials = getCredentials(req);
+    if (!credentials)
+      return returnError(new CopayServer.ClientError({
+        code: 'NOTAUTHORIZED'
+      }), res, req);
+
+    var auth = {
+      copayerId: credentials.copayerId,
+      message: req.method.toLowerCase() + '|' + req.url + '|' + JSON.stringify(req.body),
+      signature: credentials.signature,
+    };
+    CopayServer.getInstanceWithAuth(auth, function(err, server) {
+      if (err) return returnError(err, res, req);
+      return cb(server);
+    });
+  };
+
+  router.post('/v1/wallets/', function(req, res) {
+    var server = CopayServer.getInstance();
+    server.createWallet(req.body, function(err, walletId) {
+      if (err) return returnError(err, res, req);
+
+      res.json({
+        walletId: walletId,
+      });
+    });
+  });
+
+  router.post('/v1/wallets/:id/copayers/', function(req, res) {
+    req.body.walletId = req.params['id'];
+    var server = CopayServer.getInstance();
+    server.joinWallet(req.body, function(err, result) {
+      if (err) return returnError(err, res, req);
+
+      res.json(result);
+    });
+  });
+
+  router.get('/v1/wallets/', function(req, res) {
+    getServerWithAuth(req, res, function(server) {
+      var result = {};
+      async.parallel([
+
+        function(next) {
+          server.getWallet({}, function(err, wallet) {
+            if (err) return next(err);
+            result.wallet = wallet;
+            next();
+          });
+        },
+        function(next) {
+          server.getBalance({}, function(err, balance) {
+            if (err) return next(err);
+            result.balance = balance;
+            next();
+          });
+        },
+        function(next) {
+          server.getPendingTxs({}, function(err, pendingTxps) {
+            if (err) return next(err);
+            result.pendingTxps = pendingTxps;
+            next();
+          });
+        },
+      ], function(err) {
+        if (err) return returnError(err, res, req);
+        res.json(result);
+      });
+    });
+  });
+
+
+  router.get('/v1/txproposals/', function(req, res) {
+    getServerWithAuth(req, res, function(server) {
+      server.getPendingTxs({}, function(err, pendings) {
+        if (err) return returnError(err, res, req);
+        res.json(pendings);
+      });
+    });
+  });
+
+
+  router.post('/v1/txproposals/', function(req, res) {
+    getServerWithAuth(req, res, function(server) {
+      server.createTx(req.body, function(err, txp) {
+        if (err) return returnError(err, res, req);
+        res.json(txp);
+      });
+    });
+  });
+
+
+  router.post('/v1/addresses/', function(req, res) {
+    getServerWithAuth(req, res, function(server) {
+      server.createAddress(req.body, function(err, address) {
+        if (err) return returnError(err, res, req);
+        res.json(address);
+      });
+    });
+  });
+
+  router.get('/v1/addresses/', function(req, res) {
+    getServerWithAuth(req, res, function(server) {
+      server.getAddresses({}, function(err, addresses) {
+        if (err) return returnError(err, res, req);
+        res.json(addresses);
+      });
+    });
+  });
+
+  router.get('/v1/balance/', function(req, res) {
+    getServerWithAuth(req, res, function(server) {
+      server.getBalance({}, function(err, balance) {
+        if (err) return returnError(err, res, req);
+        res.json(balance);
+      });
+    });
+  });
+
+  router.post('/v1/txproposals/:id/signatures/', function(req, res) {
+    getServerWithAuth(req, res, function(server) {
+      req.body.txProposalId = req.params['id'];
+      server.signTx(req.body, function(err, txp) {
+        if (err) return returnError(err, res, req);
+        res.json(txp);
+        res.end();
+      });
+    });
+  });
+
+  // TODO Check HTTP verb and URL name
+  router.post('/v1/txproposals/:id/broadcast/', function(req, res) {
+    getServerWithAuth(req, res, function(server) {
+      req.body.txProposalId = req.params['id'];
+      server.broadcastTx(req.body, function(err, txp) {
+        if (err) return returnError(err, res, req);
+        res.json(txp);
+        res.end();
+      });
+    });
+  });
+
+  router.post('/v1/txproposals/:id/rejections', function(req, res) {
+    getServerWithAuth(req, res, function(server) {
+      req.body.txProposalId = req.params['id'];
+      server.rejectTx(req.body, function(err, txp) {
+        if (err) return returnError(err, res, req);
+        res.json(txp);
+        res.end();
+      });
+    });
+  });
+
+  router.delete('/v1/txproposals/:id/', function(req, res) {
+    getServerWithAuth(req, res, function(server) {
+      req.body.txProposalId = req.params['id'];
+      server.removePendingTx(req.body, function(err) {
+        if (err) return returnError(err, res, req);
+        res.end();
+      });
+    });
+  });
+
+  // TODO: DEBUG only!
+  router.get('/v1/dump', function(req, res) {
+    var server = CopayServer.getInstance();
+    server.storage._dump(function() {
+      res.end();
+    });
+  });
+  app.use(opts.base_path || '/copay/api', router);
+  return app;
+};
+
+module.exports = ExpressApp;
diff --git a/lib/server.js b/lib/server.js
index bc3a287..486e762 100644
--- a/lib/server.js
+++ b/lib/server.js
@@ -26,15 +26,18 @@ var TxProposal = require('./model/txproposal');
 var Notification = require('./model/notification');
 
 var initialized = false;
-var storage;
+var storage, blockExplorer;
 
 /**
  * Creates an instance of the Copay server.
  * @constructor
  */
 function CopayServer() {
-  if (!initialized) throw new Error('Server not initialized');
+  if (!initialized) 
+    throw new Error('Server not initialized');
+
   this.storage = storage;
+  this.blockExplorer = blockExplorer;
   this.notifyTicker = 0;
 };
 
@@ -45,10 +48,12 @@ nodeutil.inherits(CopayServer, events.EventEmitter);
  * Initializes global settings for all instances.
  * @param {Object} opts
  * @param {Storage} [opts.storage] - The storage provider.
+ * @param {Storage} [opts.blockExplorer] - The blockExporer provider.
  */
 CopayServer.initialize = function(opts) {
   opts = opts || {};
   storage = opts.storage ||  new Storage();
+  blockExplorer = opts.blockExplorer;
   initialized = true;
 };
 
@@ -311,6 +316,9 @@ CopayServer.prototype.verifyMessageSignature = function(opts, cb) {
 CopayServer.prototype._getBlockExplorer = function(provider, network) {
   var url;
 
+  if (this.blockExplorer)
+    return this.blockExplorer;
+
   switch (provider) {
     default:
     case 'insight':
@@ -352,7 +360,6 @@ CopayServer.prototype._getUtxos = function(cb) {
       var utxos = _.map(inutxos, function(i) {
         return i.toObject();
       });
-
       self.getPendingTxs({}, function(err, txps) {
         if (err) return cb(err);
 
@@ -773,7 +780,7 @@ CopayServer.prototype.rejectTx = function(opts, cb) {
         });
       };
 
-      return cb();
+      return cb(null, txp);
     });
   });
 };
diff --git a/lib/walletutils.js b/lib/walletutils.js
index 5aacd82..78f4c71 100644
--- a/lib/walletutils.js
+++ b/lib/walletutils.js
@@ -1,4 +1,5 @@
 var _ = require('lodash');
+var $ = require('preconditions').singleton();
 var sjcl = require('sjcl');
 
 var Bitcore = require('bitcore');
@@ -14,6 +15,7 @@ function WalletUtils() {};
 /* TODO: It would be nice to be compatible with bitcoind signmessage. How
  * the hash is calculated there? */
 WalletUtils.hashMessage = function(text) {
+  $.checkArgument(text);
   var buf = new Buffer(text);
   var ret = crypto.Hash.sha256sha256(buf);
   ret = new Bitcore.encoding.BufferReader(ret).readReverse();
@@ -22,6 +24,7 @@ WalletUtils.hashMessage = function(text) {
 
 
 WalletUtils.signMessage = function(text, privKey) {
+  $.checkArgument(text);
   var priv = new PrivateKey(privKey);
   var hash = WalletUtils.hashMessage(text);
   return crypto.ECDSA.sign(hash, priv, 'little').toString();
@@ -29,6 +32,11 @@ WalletUtils.signMessage = function(text, privKey) {
 
 
 WalletUtils.verifyMessage = function(text, signature, pubKey) {
+  $.checkArgument(text, pubKey);
+
+  if (!signature)
+    return false;
+
   var pub = new PublicKey(pubKey);
   var hash = WalletUtils.hashMessage(text);
 
@@ -69,6 +77,7 @@ WalletUtils.toSecret = function(walletId, walletPrivKey, network) {
 };
 
 WalletUtils.fromSecret = function(secret) {
+  $.checkArgument(secret);
   var secretSplit = secret.split(':');
   var walletId = secretSplit[0];
   var walletPrivKey = Bitcore.PrivateKey.fromString(secretSplit[1]);
@@ -104,8 +113,10 @@ WalletUtils.UNITS = {
 };
 
 WalletUtils.parseAmount = function(text) {
-  var regex = '^(\\d*(\\.\\d{0,8})?)\\s*(' + _.keys(WalletUtils.UNITS).join('|') + ')?$';
+  if (!_.isString(text)) 
+   text = text.toString();
 
+  var regex = '^(\\d*(\\.\\d{0,8})?)\\s*(' + _.keys(WalletUtils.UNITS).join('|') + ')?$';
   var match = new RegExp(regex, 'i').exec(text.trim());
 
   if (!match || match.length === 0) throw new Error('Invalid amount');
diff --git a/package.json b/package.json
index bcca48e..049b877 100644
--- a/package.json
+++ b/package.json
@@ -40,7 +40,8 @@
     "mocha": "^1.18.2",
     "sinon": "^1.10.3",
     "memdown": "^1.0.0",
-    "jsdoc": "^3.3.0"
+    "jsdoc": "^3.3.0",
+    "supertest": "*"
   },
   "scripts": {
     "start": "node server.js"
diff --git a/test/integration/clientApi.js b/test/integration/clientApi.js
index dea1aff..16c0288 100644
--- a/test/integration/clientApi.js
+++ b/test/integration/clientApi.js
@@ -4,133 +4,497 @@ var _ = require('lodash');
 var chai = require('chai');
 var sinon = require('sinon');
 var should = chai.should();
+var levelup = require('levelup');
+var memdown = require('memdown');
+var async = require('async');
+var request = require('supertest');
 var Client = require('../../lib/client');
 var API = Client.API;
 var Bitcore = require('bitcore');
 var TestData = require('./clienttestdata');
 var WalletUtils = require('../../lib/walletutils');
+var ExpressApp = require('../../lib/expressapp');
+var Storage = require('../../lib/storage');
+
+
+var helpers = {};
+
+helpers.getRequest = function(app) {
+  return function(args, cb) {
+    var req = request(app);
+    var r = req[args.method](args.relUrl);
+
+    if (args.headers) {
+      _.each(args.headers, function(v, k) {
+        r.set(k, v);
+      })
+    }
+    if (!_.isEmpty(args.body)) {
+      r.send(args.body);
+    };
+    r.end(function(err, res) {
+      return cb(err, res, res.body);
+    });
+  };
+};
+
+helpers.createAndJoinWallet = function(clients, m, n, cb) {
+  clients[0].createWallet('wallet name', 'creator', m, n, 'testnet',
+    function(err, secret) {
+      if (err) return cb(err);
+      if (n == 1) return cb();
+
+      should.exist(secret);
+      async.each(_.range(n - 1), function(i, cb) {
+        clients[i + 1].joinWallet(secret, 'copayer ' + (i + 1), function(err, result) {
+          should.not.exist(err);
+          return cb(err);
+        });
+      }, function(err) {
+        if (err) return cb(err);
+        return cb(null, {
+          m: m,
+          n: n,
+          secret: secret,
+        });
+      });
+    });
+};
+
+
+var fsmock = {};
+var content = {};
+fsmock.readFile = function(name, enc, cb) {
+  if (!content || _.isEmpty(content[name]))
+    return cb('empty');
+
+  return cb(null, content[name]);
+};
+fsmock.writeFile = function(name, data, cb) {
+  content[name] = data;
+  return cb();
+};
+fsmock.reset = function() {
+  content = {};
+};
+
+fsmock._get = function(name) {
+  return content[name];
+};
+
+
+var blockExplorerMock = {};
+blockExplorerMock.utxos = [];
+
+
+
+
+blockExplorerMock.getUnspentUtxos = function(dummy, cb) {
+  var ret = _.map(blockExplorerMock.utxos || [], function(x) {
+    x.toObject = function() {
+      return this;
+    };
+    return x;
+  });
+  return cb(null, ret);
+};
+
+blockExplorerMock.setUtxo = function(address, amount, m) {
+  blockExplorerMock.utxos.push({
+    txid: Bitcore.crypto.Hash.sha256(new Buffer(Math.random() * 100000)).toString('hex'),
+    vout: Math.floor((Math.random() * 10) + 1),
+    amount: amount,
+    address: address.address,
+    scriptPubKey: Bitcore.Script.buildMultisigOut(address.publicKeys, m).toScriptHashOut().toString(),
+  });
+};
+
+
+blockExplorerMock.broadcast = function(raw, cb) {
+  blockExplorerMock.lastBroadcasted = raw;
+  return cb(null, (new Bitcore.Transaction(raw)).id);
+};
+
+blockExplorerMock.reset = function() {
+  blockExplorerMock.utxos = [];
+};
 
 describe('client API ', function() {
-  var client;
+  var clients, app;
 
   beforeEach(function() {
-    var fsmock = {};;
-    fsmock.readFile = sinon.mock().yields(null, JSON.stringify(TestData.storage.wallet11));
-    fsmock.writeFile = sinon.mock().yields();
-    var storage = new Client.FileStorage({
-      filename: 'dummy',
-      fs: fsmock,
+    clients = [];
+    var db = levelup(memdown, {
+      valueEncoding: 'json'
     });
-    client = new Client({
-      storage: storage
+    var storage = new Storage({
+      db: db
     });
-  });
+    app = ExpressApp.start({
+      CopayServer: {
+        storage: storage,
+        blockExplorer: blockExplorerMock,
+      }
+    });
+    // Generates 5 clients
+    _.each(_.range(5), function(i) {
+      var storage = new Client.FileStorage({
+        filename: 'client' + i,
+        fs: fsmock,
+      });
+      var client = new Client({
+        storage: storage,
+      });
 
-  describe('#_tryToComplete ', function() {
-    it('should complete a wallet ', function(done) {
-      var request = sinon.stub();
+      client.request = helpers.getRequest(app);
+      clients.push(client);
+    });
+    fsmock.reset();
+    blockExplorerMock.reset();
+  });
 
-      // Wallet request
-      request.onCall(0).yields(null, {
-        statusCode: 200,
-      }, TestData.serverResponse.completeWallet);
-      request.onCall(1).yields(null, {
-        statusCode: 200,
-      }, "pepe");
+  describe('Wallet Creation', function() {
+    it('should check balance in a 1-1 ', function(done) {
+      helpers.createAndJoinWallet(clients, 1, 1, function(err) {
+        should.not.exist(err);
+        clients[0].getBalance(function(err, x) {
+          should.not.exist(err);
+          done();
+        })
+      });
+    });
+    it('should be able to complete wallets in copayer that joined later', function(done) {
+      helpers.createAndJoinWallet(clients, 2, 3, function(err) {
+        should.not.exist(err);
+        clients[0].getBalance(function(err, x) {
+          should.not.exist(err);
+          clients[1].getBalance(function(err, x) {
+            should.not.exist(err);
+            clients[2].getBalance(function(err, x) {
+              should.not.exist(err);
+              done();
+            })
+          })
+        })
+      });
+    });
 
-      client.request = request;
-      client.storage.fs.readFile = sinon.stub().yields(null, JSON.stringify(TestData.storage.incompleteWallet22));
-      client.getBalance(function(err, x) {
+    it('should not allow to join a full wallet ', function(done) {
+      helpers.createAndJoinWallet(clients, 2, 2, function(err, w) {
         should.not.exist(err);
+        should.exist(w.secret);
+        clients[4].joinWallet(w.secret, 'copayer', function(err, result) {
+          err.should.contain('Request error');
+          done();
+        });
+      });
+    });
+    it('should fail with a unknown secret', function(done) {
+      var oldSecret = '3f8e5acb-ceeb-4aae-134f-692d934e3b1c:L2gohj8s2fLKqVU5cQutAVGciutUxczFxLxxXHFsjzLh71ZjkFQQ:T';
+      clients[0].joinWallet(oldSecret, 'copayer', function(err, result) {
+        err.should.contain('Request error');
         done();
       });
     });
+    it('should reject wallets with bad signatures', function(done) {
+      helpers.createAndJoinWallet(clients, 2, 3, function(err) {
+        should.not.exist(err);
 
+        // Get right response
+        var data = clients[0]._load(function(err, data) {
+          var url = '/v1/wallets/';
+          clients[0]._doGetRequest(url, data, function(err, x) {
 
-    it('should handle incomple wallets', function(done) {
-      var request = sinon.stub();
+            // Tamper data
+            x.wallet.copayers[0].xPubKey = x.wallet.copayers[1].xPubKey;
 
-      // Wallet request
-      request.onCall(0).yields(null, {
-        statusCode: 200,
-      }, TestData.serverResponse.incompleteWallet);
+            // Tamper response
+            clients[1]._doGetRequest = sinon.stub().yields(null, x);
 
-      client.request = request;
-      client.storage.fs.readFile = sinon.stub().yields(null, JSON.stringify(TestData.storage.incompleteWallet22));
-      client.createAddress(function(err, x) {
-        err.should.contain('Incomplete');
-        done();
+            clients[1].getBalance(function(err, x) {
+              err.should.contain('verified');
+              done();
+            });
+          });
+        });
       });
     });
 
-    it('should reject wallets with bad signatures', function(done) {
-      var request = sinon.stub();
-      // Wallet request
-      request.onCall(0).yields(null, {
-        statusCode: 200,
-      }, TestData.serverResponse.corruptWallet22);
+    it('should reject wallets with missing signatures', function(done) {
+      helpers.createAndJoinWallet(clients, 2, 3, function(err) {
+        should.not.exist(err);
 
-      client.request = request;
-      client.storage.fs.readFile = sinon.stub().yields(null, JSON.stringify(TestData.storage.incompleteWallet22));
-      client.createAddress(function(err, x) {
-        err.should.contain('verified');
-        done();
+        // Get right response
+        var data = clients[0]._load(function(err, data) {
+          var url = '/v1/wallets/';
+          clients[0]._doGetRequest(url, data, function(err, x) {
+
+            // Tamper data
+            delete x.wallet.copayers[1].xPubKey;
+
+            // Tamper response
+            clients[1]._doGetRequest = sinon.stub().yields(null, x);
+
+            clients[1].getBalance(function(err, x) {
+              err.should.contain('verified');
+              done();
+            });
+          });
+        });
       });
     });
 
-    it('should reject wallets with missing signatures ', function(done) {
-      var request = sinon.stub();
-      // Wallet request
-      request.onCall(0).yields(null, {
-        statusCode: 200,
-      }, TestData.serverResponse.corruptWallet222);
 
-      client.request = request;
-      client.storage.fs.readFile = sinon.stub().yields(null, JSON.stringify(TestData.storage.incompleteWallet22));
-      client.createAddress(function(err, x) {
-        err.should.contain('verified');
-        done();
+    it('should reject wallets missing caller"s pubkey', function(done) {
+      helpers.createAndJoinWallet(clients, 2, 3, function(err) {
+        should.not.exist(err);
+
+        // Get right response
+        var data = clients[0]._load(function(err, data) {
+          var url = '/v1/wallets/';
+          clients[0]._doGetRequest(url, data, function(err, x) {
+
+            // Tamper data. Replace caller's pubkey
+            x.wallet.copayers[1].xPubKey = (new Bitcore.HDPrivateKey()).publicKey;
+            // Add a correct signature
+            x.wallet.copayers[1].xPubKeySignature = WalletUtils.signMessage(
+              x.wallet.copayers[1].xPubKey, data.walletPrivKey),
+
+            // Tamper response
+            clients[1]._doGetRequest = sinon.stub().yields(null, x);
+
+            clients[1].getBalance(function(err, x) {
+              err.should.contain('verified');
+              done();
+            });
+          });
+        });
       });
     });
+  });
 
-    it('should reject wallets missing caller"s pubkey', function(done) {
-      var request = sinon.stub();
-      // Wallet request
-      request.onCall(0).yields(null, {
-        statusCode: 200,
-      }, TestData.serverResponse.missingMyPubKey);
 
-      client.request = request;
-      client.storage.fs.readFile = sinon.stub().yields(null, JSON.stringify(TestData.storage.incompleteWallet22));
-      client.createAddress(function(err, x) {
-        err.should.contain('verified');
-        done();
+  describe('Address Creation', function() {
+    it('should be able to create address in all copayers in a 2-3 wallet', function(done) {
+      this.timeout(5000);
+      helpers.createAndJoinWallet(clients, 2, 3, function(err) {
+        should.not.exist(err);
+        clients[0].createAddress(function(err, x0) {
+          should.not.exist(err);
+          should.exist(x0.address);
+          clients[1].createAddress(function(err, x1) {
+            should.not.exist(err);
+            should.exist(x1.address);
+            clients[2].createAddress(function(err, x2) {
+              should.not.exist(err);
+              should.exist(x2.address);
+              done();
+            });
+          });
+        });
+      });
+    });
+    it('should see balance on address created by others', function(done) {
+      helpers.createAndJoinWallet(clients, 2, 2, function(err, w) {
+        should.not.exist(err);
+        clients[0].createAddress(function(err, x0) {
+          should.not.exist(err);
+          should.exist(x0.address);
+
+          blockExplorerMock.setUtxo(x0, 10, w.m);
+          clients[0].getBalance(function(err, bal0) {
+            should.not.exist(err);
+            bal0.totalAmount.should.equal(10 * 1e8);
+            bal0.lockedAmount.should.equal(0);
+            clients[1].getBalance(function(err, bal1) {
+              bal1.totalAmount.should.equal(10 * 1e8);
+              bal1.lockedAmount.should.equal(0);
+              done();
+            });
+          });
+        });
       });
     });
   });
 
-  describe('#createAddress ', function() {
-    it('should check address ', function(done) {
 
-      var response = {
-        createdOn: 1424105995,
-        address: '2N3fA6wDtnebzywPkGuNK9KkFaEzgbPRRTq',
-        path: 'm/2147483647/0/7',
-        publicKeys: ['03f6a5fe8db51bfbaf26ece22a3e3bc242891a47d3048fc70bc0e8c03a071ad76f']
-      };
-      var request = sinon.mock().yields(null, {
-        statusCode: 200
-      }, response);
-      client.request = request;
+  describe('Wallet Backups and Mobility', function() {
 
+    it('round trip #import #export', function(done) {
+      helpers.createAndJoinWallet(clients, 2, 2, function(err, w) {
+        should.not.exist(err);
+        clients[0].export(function(err, str) {
+          should.not.exist(err);
+          var original = JSON.parse(fsmock._get('client0'));
+          clients[2].import(str, function(err, wallet) {
+            should.not.exist(err);
+            var clone = JSON.parse(fsmock._get('client2'));
+            delete original.walletPrivKey; // no need to persist it.
+            clone.should.deep.equal(original);
+            done();
+          });
 
-      client.createAddress(function(err, x) {
+        });
+      });
+    });
+    it('should recreate a wallet, create addresses and receive money', function(done) {
+      var backup = '["tprv8ZgxMBicQKsPehCdj4HM1MZbKVXBFt5Dj9nQ44M99EdmdiUfGtQBDTSZsKmzdUrB1vEuP6ipuoa39UXwPS2CvnjE1erk5aUjc5vQZkWvH4B",2,["tpubD6NzVbkrYhZ4XCNDPDtyRWPxvJzvTkvUE2cMPB8jcUr9Dkicv6cYQmA18DBAid6eRK1BGCU9nzgxxVdQUGLYJ34XsPXPW4bxnH4PH6oQBF3"],"sd0kzXmlXBgTGHrKaBW4aA=="]';
+      clients[0].import(backup, function(err, wallet) {
         should.not.exist(err);
-        x.address.should.equal('2N3fA6wDtnebzywPkGuNK9KkFaEzgbPRRTq');
-        done();
+        clients[0].reCreateWallet('pepe', function(err, wallet) {
+          should.not.exist(err);
+
+          clients[0].createAddress(function(err, x0) {
+            should.not.exist(err);
+            should.exist(x0.address);
+            blockExplorerMock.setUtxo(x0, 10, 2);
+            clients[0].getBalance(function(err, bal0) {
+              should.not.exist(err);
+              bal0.totalAmount.should.equal(10 * 1e8);
+              bal0.lockedAmount.should.equal(0);
+              done();
+            });
+          });
+        });
+      });
+    });
+  });
+
+
+  describe('Send Transactions', function() {
+    it('Send and broadcast in 1-1 wallet', function(done) {
+      helpers.createAndJoinWallet(clients, 1, 1, function(err, w) {
+        clients[0].createAddress(function(err, x0) {
+          should.not.exist(err);
+          should.exist(x0.address);
+          blockExplorerMock.setUtxo(x0, 1, 1);
+          var opts = {
+            amount: '0.1btc',
+            toAddress: 'n2TBMPzPECGUfcT2EByiTJ12TPZkhN2mN5',
+            message: 'hola 1-1',
+          };
+          clients[0].sendTxProposal(opts, function(err, x) {
+            should.not.exist(err);
+            x.requiredRejections.should.equal(1);
+            x.requiredSignatures.should.equal(1);
+            x.status.should.equal('pending');
+            x.changeAddress.path.should.equal('m/2147483647/1/0');
+            clients[0].signTxProposal(x, function(err, tx) {
+              should.not.exist(err);
+              tx.status.should.equal('broadcasted');
+              tx.txid.should.equal((new Bitcore.Transaction(blockExplorerMock.lastBroadcasted)).id);
+              done();
+            });
+          });
+        });
       });
     });
+    it('Send and broadcast in 2-3 wallet', function(done) {
+      helpers.createAndJoinWallet(clients, 2, 3, function(err, w) {
+        clients[0].createAddress(function(err, x0) {
+          should.not.exist(err);
+          should.exist(x0.address);
+          blockExplorerMock.setUtxo(x0, 10, 1);
+          var opts = {
+            amount: 10000,
+            toAddress: 'n2TBMPzPECGUfcT2EByiTJ12TPZkhN2mN5',
+            message: 'hola 1-1',
+          };
+          clients[0].sendTxProposal(opts, function(err, x) {
+            should.not.exist(err);
+            x.status.should.equal('pending');
+            x.requiredRejections.should.equal(2);
+            x.requiredSignatures.should.equal(2);
+            clients[0].signTxProposal(x, function(err, tx) {
+              should.not.exist(err, err);
+              tx.status.should.equal('pending');
+              clients[1].signTxProposal(x, function(err, tx) {
+                should.not.exist(err);
+                tx.status.should.equal('broadcasted');
+                tx.txid.should.equal((new Bitcore.Transaction(blockExplorerMock.lastBroadcasted)).id);
+                done();
+              });
+            });
+          });
+        });
+      });
+    });
+
+    it('Send, reject, 2 signs and broadcast in 2-3 wallet', function(done) {
+      helpers.createAndJoinWallet(clients, 2, 3, function(err, w) {
+        clients[0].createAddress(function(err, x0) {
+          should.not.exist(err);
+          should.exist(x0.address);
+          blockExplorerMock.setUtxo(x0, 10, 1);
+          var opts = {
+            amount: 10000,
+            toAddress: 'n2TBMPzPECGUfcT2EByiTJ12TPZkhN2mN5',
+            message: 'hola 1-1',
+          };
+          clients[0].sendTxProposal(opts, function(err, x) {
+            should.not.exist(err);
+            x.status.should.equal('pending');
+            x.requiredRejections.should.equal(2);
+            x.requiredSignatures.should.equal(2);
+            clients[0].rejectTxProposal(x, 'no me gusto', function(err, tx) {
+              should.not.exist(err, err);
+              tx.status.should.equal('pending');
+              clients[1].signTxProposal(x, function(err, tx) {
+                should.not.exist(err);
+                clients[2].signTxProposal(x, function(err, tx) {
+                  should.not.exist(err);
+                  tx.status.should.equal('broadcasted');
+                  tx.txid.should.equal((new Bitcore.Transaction(blockExplorerMock.lastBroadcasted)).id);
+                  done();
+                });
+              });
+            });
+          });
+        });
+      });
+    });
+
+    it('Send, reject in 3-4 wallet', function(done) {
+      helpers.createAndJoinWallet(clients, 3, 4, function(err, w) {
+        clients[0].createAddress(function(err, x0) {
+          should.not.exist(err);
+          should.exist(x0.address);
+          blockExplorerMock.setUtxo(x0, 10, 1);
+          var opts = {
+            amount: 10000,
+            toAddress: 'n2TBMPzPECGUfcT2EByiTJ12TPZkhN2mN5',
+            message: 'hola 1-1',
+          };
+          clients[0].sendTxProposal(opts, function(err, x) {
+            should.not.exist(err);
+            x.status.should.equal('pending');
+            x.requiredRejections.should.equal(2);
+            x.requiredSignatures.should.equal(3);
+
+            clients[0].rejectTxProposal(x, 'no me gusto', function(err, tx) {
+              should.not.exist(err, err);
+              tx.status.should.equal('pending');
+              clients[1].signTxProposal(x, function(err, tx) {
+                should.not.exist(err);
+                tx.status.should.equal('pending');
+                clients[2].rejectTxProposal(x, 'tampoco me gusto', function(err, tx) {
+                  should.not.exist(err);
+                  tx.status.should.equal('rejected');
+                  done();
+                });
+              });
+            });
+          });
+        });
+      });
+    });
+
 
+  });
+
+
+  /*
+  describe('TODO', function(x) {
     it('should detect fake addresses ', function(done) {
       var response = {
         createdOn: 1424105995,
@@ -151,25 +515,6 @@ describe('client API ', function() {
   });
 
 
-  describe('#export & #import 2-2 wallet', function() {
-    it('round trip ', function(done) {
-      client.storage.fs.readFile = sinon.stub().yields(null, JSON.stringify(TestData.storage.complete22));
-      client.export(function(err, str) {
-        should.not.exist(err);
-
-        client.storage.fs.readFile = sinon.stub().yields(null);
-        client.import(str, function(err, wallet) {
-          should.not.exist(err);
-          var wallet = JSON.parse(client.storage.fs.writeFile.getCall(0).args[1]);
-          TestData.storage.complete22.should.deep.equal(wallet);
-
-          done();
-        });
-      });
-    });
-  });
-
-
   describe('#getTxProposals', function() {
     it('should return tx proposals and decrypt message', function(done) {
       client.storage.fs.readFile = sinon.stub().yields(null, JSON.stringify(TestData.storage.complete11));
@@ -188,10 +533,6 @@ describe('client API ', function() {
     });
   });
 
-  describe('#recreate', function() {
-    it.skip('Should recreate a wallet acording stored data', function(done) {});
-  });
-
   describe('#sendTxProposal ', function() {
     it('should send tx proposal with encrypted message', function(done) {
       client.storage.fs.readFile = sinon.stub().yields(null, JSON.stringify(TestData.storage.complete11));
@@ -261,4 +602,5 @@ describe('client API ', function() {
       });
     });
   });
+ */
 });
diff --git a/test/integration/server.js b/test/integration/server.js
index 92490db..cf5e799 100644
--- a/test/integration/server.js
+++ b/test/integration/server.js
@@ -20,7 +20,6 @@ var Copayer = require('../../lib/model/copayer');
 var CopayServer = require('../../lib/server');
 var TestData = require('../testdata');
 
-
 var helpers = {};
 helpers.getAuthServer = function(copayerId, cb) {
   var signatureStub = sinon.stub(CopayServer.prototype, '_verifySignature');