Mobile carrier AT&T has one sweet deal for its customers who travel abroad more often. The Internationa Day Pass plan costs $10 a day and gives unlimited text and talk plus access to your data plan.
The plan is available when traveling to more than 100 countries, neatly listed by the company in the list linked below.
To use it, you just need to contact Customers Service and activate it. It will be active until removed and kicks in the moment you turn on your device after landing in the desired location.
AT&T's fair use policy says that if the international text, voice or data exceeds 50% of total data for two consecutive months, it may need to disable it for your number.
That's only possible if the device you are using is unlocked. If the device is still being paid for or if an unlock request was never submitted, non-AT&T SIM cards will not work.
You had that in Canada for a while, and it is the same fare (10CAD $), but you get unlimited data too. Plus it activates via an SMS when you enter a new country. And it tops at 100$, so after 10 days you can still have unlimited data, but because of ...
Greedy, very expensive, cheating. Buy local SIM Card instead , much much cheaper especially in Asian or European countries.