t-mobile, iphone, data plans, and wi-fi?

i'm thinking about purchasing an unlocked iphone to use on t-mobile but i don't wanna pay for a data plan. is it possible to access the internet thru wi-fi connection without getting charged ridiculous amounts of money for data usage? i'm only gonna have talk and text on my plan. i've heard and read that its possible but how can i make sure i won't get charged for data usage by t-mobile?
 
Back
Top