The following steps work on Ubuntu 16.04.
1. Get source from https://github.com/guardianproject/Orfox.git
2. Install Android SDK 23, SDK Build-tools 23.0.1, Android Support Repository
3. Export ANDROID_HOME, ANDROID_NDK_HOME
4. In root folder, execute (note: if need to build modified code, first comment out the git part)
./make_build_release
5. If error “Could not find autoconf 2.13”, install autoconf-2.13 from source. e.g. on Ubuntu 16.04:
wget http://ftp.gnu.org/gnu/autoconf/autoconf-2.13.tar.gz tar -xvzf autoconf-2.13.tar.gz cd autoconf-2.13/ ./configure --program-suffix=2.13 make sudo make install'
6. If error “ccache not found”,
apt-get install ccache