which is better samsung s2 or iphone 4s?

as soon as it hits march im due for an upgrade and im looking at the samsung galaxy s2 for att. but i read comparisons online and it seems that the samsung galaxy s2 is the top phone, but some reviews state that iphone 4s is better, and some say samsung galaxy s2 is better. what are pros and cons of each phone? im a teenager and i mainly use it for texting, call parents, some games, internet, and typical teen stuff. i go to school and run so i dont think battery will be an issue. i use itunes, but i have an ipod too so music is not a problem.