Will a Iphone3gs work for Tmobile?

Annalia

If I bought a iphone 3gs could I just switch my sim card from my old phone over to it?

Don

As long as it is either unlocked or if it was originally locked to T-Mobile it will work

SSP Bowl Dude

It needs to be unlocked. The iPhone uses a mini SIM, so you may need to cut it down or get a different one.

You will be limited to EDGE (2G) data and MMS won't work well.

Will my sim card for tmobile work for at&t? Well i have a tmobile sparq and an iphone 3gs and only can use my tmobile phone. Is there any way i can put my tmobile sim card into my iphone? And also i do not know how to unlock any one of my phones
Will a sim card from tmobile work in a Virgin Mobile iphone 4s? The virgin mobile iphone 4s has a sim card slot, so if i put a tmobile sim will it work? If the iphone isn't activated with a virgin mobile. Or if i buy a iphone 4s from the apple website without any service will it work with virgin mobile?
Why I can't download ''Calendar Converter App'' in Iphone3Gs? I can buy a app it cost $1.99 and I'm interesting on it, it says it need to be updated to iOS 7 and I knew there's no iOS7 for Iphone 3Gs I try to email the developer but it won't reach.
Why does my Iphone3GS crash when i play games? Every game i play in my Iphone 3GS it crashes and sends me back to the home screen, i played these games before and never crashed, now every other game it crashes with the exception of Angry Birds, that i can play normally. All the other games even these who never crashed before as above, all freeze and crash. How can this be fixed?