The apk is from this thread
http://xdaforums.com/crossdevice-dev/sony-themes-apps/mod-xperia-camera-unlocked-t3071161/page57
Dont follow de instrucctions, only take de apk (v4)but others work to) and install. Try, if like to you, integrate in system with TB, link2sd,LP etc
Show 20MP but work in 13MP (9MP in 16/9) in superior auto. If any person want change 20MP to 13MP with a apk editor..,, my apk editor give me a error when make this change.