I also rolled back to 2.9.1, had no problems flying but couldn't access special flight modes.I had to go back to 2.9.1. The app kept crashing on me every 30 seconds or so. It didn't affect the flight or anything I just don't like the fact I was randomly flying blind. I'm using a Google Nexus 6P on Android 7.0. Before the update it worked perfect. I tried to uninstall and reinstall and still the same problem. Went back to 2.9.1 and it works again.
I really wish DJI would go the Gopro route of just having a controller with a screen, rather than the incompatibility and display issues with phones.
They're obviously incapable of producing a single app that works with all phones, so why not just build their own display, with high brightness and a low reflective glass?
I will try that ..furthermore, I uninstalled the previous version of DJI GO and deleted the folder DJI. After this I installed the new version with no problems