i am trying to build android game from this libgdx based games but the android app crashes when ported to android game the libgdx code i downloaded from http://rengelbert.co
I encountered the same problems and found a solution:
1) Open project settings of the project "FroggerLibGDXDesktop"
2) Go to "Java build path" / "Order and export"
3) Check all the jar files
4) Open project settings of the project "FroggerLibGDXAndroid"
5) Go to "Java build path" / "Order and export"
6) Check at least the "gdx-backend-android.jar" and the project "FroggerLibGDXDesktop"
Run the android app in emulator. Worked for me.