Mobile phone

I've not used a Samsung Galaxy S2, but the iphone4 is really rather pretty good in my opinion! It helps that a majority of my friends have an iphone, so certain apps I can use between phones via the wifi. Of course it doesn't come cheap also, Apple products are never cheap, I just paid £299 to upgrade to a white iphone4 for the missus after lots of nagging from her!
 
+1 for iPhone. An android phone can do pretty much everything an iPhone does for for less money, but the iPhone is much smoother and more polished.
 
+1 for iPhone. I only have the 3G but am looking to upgrade where as my brother got a blackberry curve for his birthday and has wanted to trade for my phone from day 1.