Originally Posted by
aceman
Another important thing to consider is to switch off data roaming on your iphone, so that you dont accidentally run up a large tab if you wander out of range of your mifi device.
OP is on Tmobile US. If he got Tmobile One plan, roaming is free actually very useable (128kbps to 256kbps) depending on the plan. But turning off roaming on other carrier is great advice. Once we were at aruba with AT&T. My wife didn't think and turn off airplane mode. By the time she told me, it was 15 min later... and she wasn't even using the phone... the idle data from apps costed like $60. I had her roaming turned on because we were in Mexico and AT&T has free data there.