I'm looking for a new one myself, but the kind of phone you want depends on your budget and what you want to do with it. If you want apps, Android or iPhone. Do you want a lot of apps at the same time? Galaxy S3 or iPhone, but if you don't actually need the apps you could buy a cheap android phone like the LG Optimus series.
I'm actually more drawn to Nokias, and especially the N8 because of the camera. Great business phones, and with the Symbian Belle OS not as hard to navigate as it used to be.
Iphone if you only wish to phone and use gps and other basic features. (Iphones are great and user-friendly, very few crashes/problems, best interface in my opinion)
Android if you like to tweak things and have a little more freedom/advanced features (like controlling and DSLR, not being bond to itunes to move files around your phone, use the phone as a USB key and so on...)
It's a matter of what you'll do with your phone really
Samsung Galaxy S II, perfect size, darn fast - okay, there are faster phones, but this one is fast enough practically for any usage, only few games even try to use quad-core processors - looks nicely, and is pretty cheap as S III was already released. Only problem with it? Battery life, which likes to misbehave. In theory it works up to 2 days, but you just have to charge it every day.
Aaaand there are hundreds of AOSP/AOKP/CM ROMs and kernels out there, so if you want to get 120% out of your device, it just sweet. Flashing and recovering soft-bricked devices is heavenly easy too.
I'am going to have to suggest have to suggest the Sony Xperia S, best phone I've ever owned, decent battery life and solid internals, on top of this it has a solidity that most phones just don't seem to offer these days the masses . My only negative point is that the glass seems to scratch rather easily but that can be rectified by getting a case or a screen protector.
I'm actually more drawn to Nokias, and especially the N8 because of the camera. Great business phones, and with the Symbian Belle OS not as hard to navigate as it used to be.
Android if you like to tweak things and have a little more freedom/advanced features (like controlling and DSLR, not being bond to itunes to move files around your phone, use the phone as a USB key and so on...)
It's a matter of what you'll do with your phone really
When they break, they do it well. I've seen that time and time again with my sisters iPhone, however I am yet to have a problem with mine.
The screen is quite fragile so get a soft + hard cover if you're getting an iPhone, but the performance and functionality are great.
Aaaand there are hundreds of AOSP/AOKP/CM ROMs and kernels out there, so if you want to get 120% out of your device, it just sweet. Flashing and recovering soft-bricked devices is heavenly easy too.