I don't have an Android, I have ipod touch 3G and Iphone 4S. I will name apps you might like but I cannot guarantee that they are on the android store :S
ORC Vengeance: free hack n slash game
NFL Pro 2013: free national football league game
Battle Bears Royale: free action/shooter game with bears
Dead Trigger: free zombie killing FPS
Absolute RC Plane Sim/ Absolute RC Heli Sim: free remote control flying simulator
Epic Citadel: free graphics tech thing, so you can see what visuals your system can run
Six Guns: free open world western game
GT Racing: free racing game
Toyshop Adventures: free fun platformer game kinda like LBP
Graal Online: free 2D mmo, plays a bit like zelda, but online
Sevenswords: free 3D mmo, the best free one
OTHER GREAT GAMES THAT MIGHT BE FREE:
Stranded: Mysteries Of Time
Banzai Rabbit
Appzilla
Paper Pilot