Sign apk

http://developer.android.com/tools/publishing/app-signing.html

Use android studio, create new key and sign...

[Note] "C:\Program Files\Java\jdk1.8.0_25\bin\jarsigner.exe" -verbose -sigalg SHA1withRSA -digestalg SHA1 -keystore
PATH\TO\YOUR\KEYSTORE\android.jks
XXX.apk
YOUR_KEY_ALIAS

[Note] need to align after signed, sdk\build-tools\build-tools-21.1.2\zipalign.exe
[Note] check apk info, sdk\build-tools\build-tools-21.1.2\aapt.exe dump badging XXX.apk