Hi,
The wifi connection itself has nothing to do wit att. They can only control your data use thru them. If you have att and the htc then i would assume you would use the unlimited data anyway soince you need it to push email ect. Things you wouldnt have a wifi connection for 24/7 unless you live in an awsome spot with round the clock hotspots. Not very likely thou
I think what your really asking is is wifi really free? well mostly no..what it is is a general access internet. Like all mcdonalds have wifi hotspots. it is for the employees. they have a username and password to access it where they go, mcd's to mcd's. Now if you want you can pay mcdonalds to access thier hotspot. ususlly pretty and they give you a username and password. That is most likely why you cant get anywhere, you dont have access even thou you are in a hotspot, so if you are living next to them then this might be a great option for you. But most of us will only use wifi in the starbucks we go to every coffee and lunch break.
As far as the data goes..if you have att get the unlimited data plan. it will save you headache as you will most definatly use internet and you dont want a 500 buck phone bill. If you dont have att and just have an at brandedphone dont worry about it.
Hope ithelps :-)
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