I tested by an outside flight but it was laborious, the helicopter being extremely lightweight, the slightest gust of wind it crash.
I went indoors and there is just GORGEOUS!
The charging / recharging is done by USB port, the red LED which lights up on the USB plug warns that the battery is charged to 100%.
The manufacturer claims 6-7 minutes flight with charged battery, I held 10 min for the first time.
As soon as you see against the helicopter no longer rises, there is no point to hound, turn off and recharge.
I highly recommend it, the price is very attractive!