I haven't tested many pool games available for Android phones but Pool Break Pro was one of the best pool games I have ever played on any device. The app is actually not just one pool game but over ten different variations of billiard-type games.
Players can choose from pool, snooker, carrom, and crokinole. Within each of these categories are a few different variations of that particular game type. The controls for the game are extremely precise and the game could easily have the best physics in a billiards game on Android. In fact, the app offers an almost infinite amount of ways to customize the experience down to the friction of the carpet on the table.
For a really cheap app, this game was packed with plenty of features and so many ways to play that you could literally stay busy for hours. Players can play online, against the computer, or even with a friend.
Overall, this app was amazing and definitely worth the low price paid. Check it out.