I need an external battery pack and I want one that is actually directly compatible with the rezound. I tried the verizon version which is a Motorola and it is crap; it couldn't even charge the phone 50% before going dead itself. A friend who has an iphone has a pack that gives him 2-3 full phone charges. Now I think that the rezound may be a bit more demanding but I don't know for sure. Also the rezound has a unique connector, so some of the battery packs don't directly connect and I would need to carry the cord with me. Any advice will be appreciated.