You do have to power it on before starting off but it charges fine through the USB connection. I leave mine connected to USB so I never have to think about charging it. There is a 5-minute auto-shut off as long as no devices are still connected to it. If it still has a Bluetooth connection going, it won't turn off. As a result, I just manually turn mine on and off. This works fine for me because I'm usually using the Sena system for music in my helmet headset and not activating the mPow for music through the bike audio system.