The Ask Homework app has come a long way since the first iOS release over a year ago. Thanks to a ton of feedback from the Pinball Arcade Fans forums the app has been tuned a lot by the developer. Finally it has been released on Android and it really plays well. It has good physics and a night mode - best lighting I have seen on Android to date. There are a lot of in app purchases, but Gold gives everything including 28 great Zac tables, night mode, physic adjustments, customisable cameras, worn playfield options, metalfx, and glass reflections. It also includes a few Zacarria EMs still to be released. More physics improvements also coming.
https://play.google.com/store/apps/details?id=hu.magicpixel.Zaccaria
A lot of discussion here:
http://pinballarcadefans.com/showthread.php/8446-Zaccharia-for-Android-Initial-Release-Discussion/page5