I am using a FreedomPop sim card. The base plan is 200MB, 200 minutes and 500 messages. And it is free. Like free free. You buy the sim once, but usually you can google a current deal to drop that down from like $10 to like $1 and you usually get a free "premium" month on top. If you want more, $20 gets you 1GB of data and unlimted messages/minutes. For $5 a pop you can step that up one gig at a time to $35 for 4GB. You can downgrade back to the free plan every month. But, read the Cons before jumping at it!
Pros:
- free / cheap
- sim at whichever size you need
- uses both T-Mo and ATT networks for a decent coverage
- oh yeah, have I mentioned that all their plans include international roaming to multiple countries? I'm using it in Germany too.
Cons:
- to keep the sim/number active, you need to use 5MB/month
- this is effectively a DATA ONLY SIM! Yes, calling and texting is VoIP!
- special app required to be installed on your phone (from the play/app store) that acts as your calling app (via changing default app that can remain installed and inactive when not needed)
Other:
- I personally am having trouble changing my plan back from free to a paid one right now, since it claims an issue with my billing information, but it might have an issue with the German credit card, it worked just fine with only paypal last year..!?
- The one time I needed support to get it going last year, phone support was not great, but in the end helpful.