I've only used my C11s for 5 months and battery problems are already here. First of all, the battery capacity is 3000 mAh, but it drains so fast that it feels like a 1500 mAh. A phone of 2018 should have 4000 mAh. Sometimes the battery percentage suddenly drops from 50% to 30%. I've tried to calibrate it but there is no way it could work. The gpu Adreno 505 is for low-end devices, how could it be on this kind of phone? The camera quality is so fking bad! My 4G is supposed to be okay for viewing websites and playing games from servers near where I live, but this dumb-ass phone has a limited bandwidth and I can't change it manually. Go to hell, Chinese noobs from Wiko. If you don't know how to make phones, don't make any.