I have a T-Mobile prepaid mobile account and would like to change my current phone. Are there any good GSM smartphones (which take a T-Mobile SIM card) which will allow me to connect to the internet via WiFi to do some simple internet browsing? I am not interested in getting any data plan... but I've read that some phones require a data plan to get setup properly for any internet usage. Are there any phones which don't require a data plan?