Yes it is underpowered, it’s no where close to the flagship phones that we are used to. So the best thing in my experience is to run one or two apps at a time max. DJI apps are very resource hungry and many of the disconnects happen because you have something running in the background. In developer options you can adjust these settings. As to root, it will basically allow you to install whatever app you want. But I would advice against a custom rom or kernel as I’m not sure of the hardware inside. The rooted
sc will take you up to 8 miles and back without issues. Hence as it is basically a radio I would not expect it to do much more. if you want some more juice, the
phantom 4 battery works very well as an add on for the
mavic 2 pro. It’s almost 10K mAH. Remove the plastic covers and all etc.