I am still waiting to get my phone on July 1st, coming from nexus s 4g, but as far as data roaming, go under the wireless settings, to mobile data, roaming, ur looking for an option called roam guard. If u turn off roam guard it won't altett u every time. It might also have roam notification or always roam options, mess with those as well. This is all on nexus s so I'm guessing its in gsiii too, good luck. Signal, might just be sprint signal, but hopefully its just indicator issue like previous phones. Best of luck on all the rest tho
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