So in a few months, I will get an iPhone. It's not from the apple store or anything, so I don't think it'll have warranty or whatever. Which is alright, cause I barely drop my phone or loose it. But my service thing is tmobile, so can I use the tmobile sim card for the iphone? Is there a specific plan I need to get? And I heard about jailbreaking. What is it exactly, and how can it be done? Please help, thanks.