I just purchased my Osmo Mobile 2 Gimbal for my iPhone 8 Plus, and loving it so far!

Simple question, I know you can charge your phone via the Osmos usb port while filming which is an awesome feature...The gimbal is stated to have 15 hours of battery life which is plenty, but I just wondered how long it would last with the iPhone plugged in? If it takes a few hours off the gimbal then I'm fine but if it really does impact more I'm going to think about mounting an external battery to the side handle somehow.

Another quick one, a right angle lightning cable will add a few milimetres to the end of the phone, will this weigh the gimble too much on the opposing side? I have ordered a counter weight but just wondered if this will impact without?

I was shooting Time Lapse with my OM2 and iPhone 8. Thought it would be a good idea to charge the phone from the gimbal USB power. The draw of the phone, while recording video, killed the gimbal battery within an hour or two. The rest of the video was a shot of the sky, when the gimbal ran out of power. In fact, I got more time if I simply shot the video without charging the phone.