hi,  
 
so I recently started to get into buying games for my iphone I am currrently playing plants vs zomnies, peggle, tilt to live and diner dash,  I was wondering if anyone could recommend some games along those lines,  I seem to have gotten my girlfriend addicted to plants vs zombies so I am looking for some more casual games to play. 
 
thanks

Examples of casual games Doodlejump, falldown, flight control and tiki titems

Angry Birds is amazingly simple, addictive and then gets super hard to 100%. It's about £0.59 too.

My favorite is Orbital. Really fun game. Freeverse Skee-ball is really addictive. Canabalt is fun. I've put a lot of time into Puzzle Quest for the iPhone as well.

Free: Defender KaW (browser based strategy?)
Free: Eliminate (4 player Online FPS, really good connection speed even over 3g!) 
Free: TapTap revenge 3 (guitar hero/rockband style rythmic game with tons of licenced music) 
 
Zenonia 2 (RPG)
FREE TODAY ONLY! - Heavygunner 3D

Puzzle Quest. It's cheaper than any other version, runs perfectly well and the gameplay isn't hampered by the interface like on just about every other iPhone port.
 
Trism and Rolando are pretty good too.

Angry Birds, Cooking Mama, the old Real Racing, COD Zombies, Canabalt, 2XL ATV Offroad, Peggle, PvZ, Bejeweled 2, Sonic the Hedgehog 2, SF IV. just to name a few.

Some guy did a pretty good review of Linkin Park 8-Bit Rebellion and apparently it's pretty good if you're a Linkin Park fan.  Personally I'm not much of a fan and it still looked like it would have been a pretty good time killer.