Exchange defective TMobile iPhone 5S

[Stevessvt]

So my wifes iPhone 5S has been a battery hog and dropping calls, and dropping signal. Ive already performed a restore to no avail. Its time to swap it out. Can I walk in to an Apple store and swap it out, or must I go through TMobile?
Thank you

 

[lolkthxbai]

So my wifes iPhone 5S has been a battery hog and dropping calls, and dropping signal. Ive already performed a restore to no avail. Its time to swap it out. Can I walk in to an Apple store and swap it out, or must I go through TMobile?
Thank you

Make a reservation for the Genius Bar online at Apple.com and make sure you've updated to the latest firmware and backed up your phone before you go.

 

[Stevessvt]

OK, will do. Thank you.