Can I switch my T-Mobile SIM card to a phone that needs a data plan?

I have the Gravity phone from T-Mobile and I wanted to switch it to a phone that requires a data plan. I'm not sure if I switch it if they would know the difference or if it'll charge me more. I know I'm able to do it because it's a SIM card, but would I be charged an additional fee without knowing?Can I switch my T-Mobile SIM card to a phone that needs a data plan?
Yes, you can switch it. They won't know that the sim is in a smartphone unless you tell them. You will not be able to access the data network unless the phone has the proper settings in it, and is unlocked (or if it's locked to T-Mobile). You should be able to make phone calls and send text messages immediately.



Be sure you know how much data you're using; if you're not on a data plan and use data anyway, the cost can mount up VERY quickly.