I've bought a 3500 mah battery around a month ago for around 15 euro including the delivery. So far I'm impressed. I went on a trip and playing constantly heavy games, listening to music and 50 percent brightness, it lasted around 7 hours doing all those things I've listed so far. I after it got drained, i changed back to the old stock One. The only thing that bothers me is that the phone got thicker twice cause of the battery being so thick.
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