There actually is a bug report regarding this issue:

http://sourceforge.net/p/scummvm/bugs/6108

It's concerning the Wii-Version, but the problem is exactly the same on Android. Unfortunately it looks like the bug wasn't solved.

Hello everyone, I recently installed ScummVM on my Nexus 7 - everything runs smooth so far, very good work! A small issue though: When playing FMTowns-Games like Indy 4 or Zak, the mouse cursor is encased in a blue box. This makes it a bit difficult to see where you're clicking. Is there any solutio...