No you will not be charged. Your phone (at least sprint) will connect to wifi if you do that. I don't see a reason why Tmobile would set it up to use their data if you are using wifi.
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Originally Posted by ClintEastwood.
your mumma's wear dirty g-strings to work, nuketown is buckin hell sick, show some love you hamburger's. double up bubble up. peace out. p.s nuketown is the shiznit, like your mumma's beef strogganoff.