Zen Table Tennis
From Reset Games (available cross platform), there's both lite and paid for versions of a simple yet classic game. It works reasonably well on a touchscreen phone but has its fair share of faults (read or watch the (video) review linked above) which I entirely agree with.
There are other table tennis games for android but they are graphics heavy so will run very poorly on 1.5 type release devices without all the Snapdragonesqueryness of later 2.1+ phones. Worth a look though I'd love to see a proper bug update before paying for it.
Chessdroid by Alberto Alonso Ruibal is well worth a butchers (as it's a lot more scalable in difficulty than many others - easy is proper easy etc). Makes you look smarter than you actually are when you're playing too, well worth the 99 (euro) cents. The free demo version only has one difficulty setting and that's clearly designed to humiliate the player as much as humanly possible. Clever way to get people to pay I guess...