This all depends on how you use TextMe.
You do not need any credits if you only plan on calling and texting other TextMe users.
Additionally, texting non-TextMe users within the US and Canada is also free!
You need credits if you plan on calling non-TextMe users, or texting and calling non-TextMe users abroad.
Call rates vary per destination. You can find out how much your call will cost by dialing the number! The rate can be seen below the number!