I have an S8+ on Nougat 7.0. Latest firmware and version of GO 4 app. It has been faultless for the past couple of weeks now, with roughly 4 hours of flying time.
By comparison, I previously had an S7 Edge and it was riddled with crashes. It really knocked my confidence with the drone. The only thing really to have changed since then (other than the new phone) is a new firmware update, which I think was .900?
I don't have any particular settings or a ritualistic way of turning each device on or off. The screen is in quad HD and I allow Android to stretch the DJI app to full screen. I turn aeroplane mode on, clear all other apps and allow the app to run when I plug in the remote. Oh, I think I have USB debugging turned on as well.