I play dinosmash and cliffed once in awhile for quick distractions. Both are real-time multiplayer game done right.
I think Durak deserves a mention if you're at all into card games - it's entertaining, and pretty easy to learn. Feels like there can be a fair amount of luck, though probably I haven't played it enough. Graphics and design are very intuitive and pleasing. Uno is online too... And Charadiam/Depict are both great - personally I prefer the latter - love the pixel-art feel, even if the game (on the whole) is more restrictive.
Assassin's Creed 2 Multiplayer on the iphone is one of the best mp game i've played in a while and I recommend trying that out when it works.
