first of all, this isn't a battery that you use in your phone, its just an external battery pack that you can connect your phone/ipod/psp/camera to via cable to charge. I like this because i dont have to make my phone bulky with a bigger back cover to accomodate for the bigger battry because i dont always need a bigger battery. Usually charging evrrynight is good enough, however, when i go out on a long trip then i keep this compact device with me and comes in handy! I would definately reccomend it. I got it on amazon for $30. Its not too big considering that its 5600 mahs!
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