Not an expert, but I'm pretty sure it is drawing power from the wall. My understanding is it is not great for the battery to act as a pass-through for power. M

Not an expert, but I'm pretty sure it is drawing power from the wall. My understanding is it is not great for the battery to act as a pass-through for power. Many cheaper devices warn you not to use the device while charging, because they don't invest in the circuitry to bypass the battery while plugged in.