Switching carriers with an old phone (Sprint Evo to T-mobile)

DaveXA said
T-Mobile has a no contract plan, $30/month, 100 mins talk, unlimited web and text. I don't want a contract. If I can find a cheap used T-Mobile compatible phone, I'm good to go. I just wish I could use my old Sprint HTC Evo phones, but it doesn't look promising.

Monthly 4G Prepaid Plans | Compare Prepaid Data Plans | T-Mobile

Just buy an unlocked quad-band GSM phone of your liking (there are plenty available at online retailers), or buy a T-mobile prepaid phone and use the new SIM they give you.