One thing i noticed it does, and all battery cases may do this, but when charging the case/phone combo, it charges the phone first (that's normal), then the case second, but when the case is charging, the phone is no longer charging. So my phone actually dropped a few percentage points while the case charged. Once the case was charged, then it started charging the phone again. It makes sense, just was interesting to see it work. Leaving it plugged in most of the day today to ensure the battery is fully charged. Will begin a full battery drain test starting tomorrow.