This is a new android-ffmpeg project since it seems there were so many different ways of doing it, it was confusing.  So here is my clean, easily changeable, static ffmpeg creator for Android.  The result is a single 'ffmpeg' that is statically linked, so its the only file you need.  setup -----
1. Install the Android NDK r8 or newer  2. On Debian/Ubuntu, run: apt-get install yasm bash patch make gawk
  (If you are on older releases of Debian/Ubuntu/Mint, like Debian/squeeze,
  then you will need to get newer versions of the packages automake,
  autotools-dev, and libtool.  You can download these from testing and
  manually install them. These are needed to provide the newest version
  of config.guess and config.sub, which only recently got Android support)
building --------  cd android-ffmpeg git submodule init git submodule update NDK_BASE=/path/to/android-ndk  ./configure_make_everything.sh  That should give you command line binary ffmpeg/ffmpeg, which is the only file you should need.
Note: the 'make' build is setup to work with the Android NDK r8e. If you are using an older version, or you are using the 32-bit NDK on a 64-bit system, then you might need to set some variables manually as part of the command line.  For example, using the 32-bit NDK on a 64-bit system:

NDK_PROCESSOR=x86 ./configure_make_everything.sh
Or using an older compiler version:

NDK_COMPILER_VERSION=4.4.3 ./configure_make_everything.sh
customizing -----------  If you want to change which coders, decoders, muxers, filters, etc that are included, edit configure_ffmpeg.sh and add/substract what you want.
sources of inspiration ----------------------  https://github.com/mconf/android-ffmpeg https://github.com/halfninja/android-ffmpeg-x264 https://github.com/guardianproject/SSCVideoProto http://wiki.multimedia.cx/index.php?title=FFmpeg_filter_howto
testing -------  # embedding metadata into a matroska video /data/local/ffmpeg -y -i test.mp4 \
  -attach attach.txt -metadata:s:2 mimetype=text/plain \
  -acodec copy -vcodec copy testattach.mkv  # video redact only ./ffmpeg/ffmpeg -y -i test.mp4 \
  -filter:v redact=redact_unsort.txt \
  -acodec copy \
  output-test-vf_redact.mp4  # audio redact only /data/local/ffmpeg -i test.mp4 -t 10 \
  -filter:a aredact=aredact_unsort.txt \
  -acodec aac  -b:a 32k -strict experimental \
  -y output-test-af_aredact.mp4  # redact audio and video /data/local/ffmpeg -i test.mp4 \
  -af aredact=aredact_unsort.txt \
  -vf redact=redact_unsort.txt \
  -acodec aac  -b:a 32k -strict experimental \
  -vcodec libx264 \
  -y output-test-redact.mp4  # tweaking h264 output settings ./ffmpeg \
  -i sscvideoproto_nexuss_high_quality_2_3_3.mp4 \
  -acodec copy \
  -vcodec libx264 -b:v 1000k -an -f mp4 \
  -y /tmp/output.mp4  # drawtext test ./ffmpeg \
  -i test.mp4 \
  -fflags +genpts -t 600 -r 8 -s 640x480 \
  -vf drawtext="fontfile=DejaVuSans.ttf:x=70:y=455: \ text='\%H\:\%M\:\%S | \%a \%d/\%b/\%Y | S500ATV | camera 0': \ fontcolor=0xFFFFFFFF:fontsize=18: \ shadowcolor=0x000000EE:shadowx=1:shadowy=1" \
  -b:v 1500000 -r 8 \
  -acodec copy \
  -y video_file.mp4