(Note: Currently it supports only on Honeycomb tablets, but it might come to your dual-core phone soon!)
Safari HD takes the Bejeweled concept to the next level, by making you stroking along an arbitrary number of adjacent animals of the same type. Spiced up with OpenFeint and rounded up with nice sounds, it puts you right into the heart of Africa.
ZDefense is an extremely challenging Tower Defense game, that sports amazing graphics, perfectly smooth performance and excellent leveldesign. It is literally fun for hours and will kill your free time, just like it killed mine.
(Note: It might remind you of HexDefense, but it was already in development, when HexDefense was not public yet.)