diff --git a/electrum/gui/kivy/tools/Dockerfile b/electrum/gui/kivy/tools/Dockerfile
index 67661da06..44887d8ea 100644
--- a/electrum/gui/kivy/tools/Dockerfile
+++ b/electrum/gui/kivy/tools/Dockerfile
@@ -4,10 +4,17 @@ FROM ubuntu:18.04
 
 ENV ANDROID_HOME="/opt/android"
 
+# configure locale
+RUN apt update -qq > /dev/null && apt install -qq --yes --no-install-recommends \
+    locales && \
+    locale-gen en_US.UTF-8
+ENV LANG="en_US.UTF-8" \
+    LANGUAGE="en_US.UTF-8" \
+    LC_ALL="en_US.UTF-8"
+
 RUN apt -y update -qq \
-    && apt -y install -qq --no-install-recommends curl unzip git python3-pip python3-setuptools \
-    && apt -y autoremove \
-    && apt -y clean
+    && apt -y install -qq --no-install-recommends curl unzip ca-certificates \
+    && apt -y autoremove
 
 
 ENV ANDROID_NDK_HOME="${ANDROID_HOME}/android-ndk"
@@ -32,6 +39,7 @@ ENV ANDROID_SDK_HOME="${ANDROID_HOME}/android-sdk"
 
 # get the latest version from https://developer.android.com/studio/index.html
 ENV ANDROID_SDK_TOOLS_VERSION="4333796"
+ENV ANDROID_SDK_BUILD_TOOLS_VERSION="28.0.3"
 ENV ANDROID_SDK_TOOLS_ARCHIVE="sdk-tools-linux-${ANDROID_SDK_TOOLS_VERSION}.zip"
 ENV ANDROID_SDK_TOOLS_DL_URL="https://dl.google.com/android/repository/${ANDROID_SDK_TOOLS_ARCHIVE}"
 
@@ -51,14 +59,13 @@ RUN mkdir --parents "${ANDROID_SDK_HOME}/.android/" \
 # accept Android licenses (JDK necessary!)
 RUN apt -y update -qq \
     && apt -y install -qq --no-install-recommends openjdk-8-jdk \
-    && apt -y autoremove \
-    && apt -y clean
-RUN yes | "${ANDROID_SDK_HOME}/tools/bin/sdkmanager" --licenses > /dev/null
+    && apt -y autoremove
+RUN yes | "${ANDROID_SDK_HOME}/tools/bin/sdkmanager" "build-tools;${ANDROID_SDK_BUILD_TOOLS_VERSION}" > /dev/null
 
 # download platforms, API, build tools
 RUN "${ANDROID_SDK_HOME}/tools/bin/sdkmanager" "platforms;android-24" > /dev/null && \
     "${ANDROID_SDK_HOME}/tools/bin/sdkmanager" "platforms;android-28" > /dev/null && \
-    "${ANDROID_SDK_HOME}/tools/bin/sdkmanager" "build-tools;28.0.3" > /dev/null && \
+    "${ANDROID_SDK_HOME}/tools/bin/sdkmanager" "build-tools;${ANDROID_SDK_BUILD_TOOLS_VERSION}" > /dev/null && \
     "${ANDROID_SDK_HOME}/tools/bin/sdkmanager" "extras;android;m2repository" > /dev/null && \
     chmod +x "${ANDROID_SDK_HOME}/tools/bin/avdmanager"
 
@@ -71,8 +78,9 @@ ENV WORK_DIR="${HOME_DIR}/wspace" \
 # install system dependencies
 RUN apt -y update -qq \
     && apt -y install -qq --no-install-recommends \
-        python virtualenv python-pip wget lbzip2 patch sudo \
-        software-properties-common
+        python3 virtualenv python3-pip python3-setuptools git wget lbzip2 patch sudo \
+        software-properties-common \
+    && apt -y autoremove
 
 # install kivy
 RUN add-apt-repository ppa:kivy-team/kivy \
@@ -87,7 +95,7 @@ RUN python3 -m pip install image
 RUN dpkg --add-architecture i386 \
     && apt -y update -qq \
     && apt -y install -qq --no-install-recommends \
-        build-essential ccache git python2.7 python2.7-dev \
+        build-essential ccache git python3 python3-dev \
         libncurses5:i386 libstdc++6:i386 libgtk2.0-0:i386 \
         libpangox-1.0-0:i386 libpangoxft-1.0-0:i386 libidn11:i386 \
         zip zlib1g-dev zlib1g:i386 \
@@ -97,8 +105,7 @@ RUN dpkg --add-architecture i386 \
 # specific recipes dependencies (e.g. libffi requires autoreconf binary)
 RUN apt -y update -qq \
     && apt -y install -qq --no-install-recommends \
-        autoconf automake cmake gettext libltdl-dev libtool pkg-config \
-        python3.7 \
+        libffi-dev autoconf automake cmake gettext libltdl-dev libtool pkg-config \
     && apt -y autoremove \
     && apt -y clean
 
@@ -119,8 +126,7 @@ RUN chown ${USER} /opt
 USER ${USER}
 
 
-RUN pip install --upgrade cython==0.29
-RUN python3 -m pip install --upgrade cython==0.29
+RUN python3 -m pip install --upgrade cython==0.28.6
 
 # prepare git
 RUN git config --global user.name "John Doe" \
@@ -130,6 +136,7 @@ RUN git config --global user.name "John Doe" \
 RUN cd /opt \
     && git clone https://github.com/kivy/buildozer \
     && cd buildozer \
+    && git checkout 88e4a4b0c7733eec1d14c00579ec412fb59ad7f2 \
     && python3 -m pip install -e .
 
 # install python-for-android
@@ -138,7 +145,7 @@ RUN cd /opt \
     && cd python-for-android \
     && git remote add sombernight https://github.com/SomberNight/python-for-android \
     && git fetch --all \
-    && git checkout fad5dd2fdc9b116b7621470deac501e4a7c4cc11 \
+    && git checkout dec1badc3bd134a9a1c69275339423a95d63413e \
        # allowBackup="false":
     && git cherry-pick 86eeec7c19679a5886d5e095ce0a43f1da138f87 \
     && python3 -m pip install -e .
diff --git a/electrum/gui/kivy/tools/buildozer.spec b/electrum/gui/kivy/tools/buildozer.spec
index 302fae19e..30b2ff863 100644
--- a/electrum/gui/kivy/tools/buildozer.spec
+++ b/electrum/gui/kivy/tools/buildozer.spec
@@ -31,7 +31,7 @@ version.filename = %(source.dir)s/electrum/version.py
 #version = 1.9.8
 
 # (list) Application requirements
-requirements = python3, android, openssl, plyer, kivy==master, libffi, libsecp256k1
+requirements = python3, android, openssl, plyer, kivy==b47f669f44dbda4f463bcb7d2cada639f7fed3bc, libffi, libsecp256k1
 
 # (str) Presplash of the application
 #presplash.filename = %(source.dir)s/gui/kivy/theming/splash.png