First successful flight in FCC:
The signal and the overall connection was greatly improved in FCC mode. The difference was definitely noticeable even though I didn't do a range test and I've kept the drone quite close. There was some wind outside and I decided to stay at around 400m distance at max. I've never lost signal during the flight. During the flight I've switched from video to photo mode multiple times and everything seemed to work fantastic.
During I've set the maximum altitude to 500m and I've climbed up to around 350m to take some shots. I couldn't do this in CE mode. While climbing to a higher altitude, the wind got stronger and I could see the aircraft slowly drifting away but everything was under control since my intention was to descend back to 120m quite quickly after I take the photos. I had around 50% battery left, I was at a distance of around 350m and 350m in height aswell.
Suddenly the app crashes. Everything was frozen. This took me by surprise and I believe I wasted quite some time figuring out what was going on. While this was happening, the aircraft was slowly drifting away as mentioned above. While being in a complete state of panic, I've initiated the failsafe RTH, flicking the S2 switch twice. I'm quite glad I did because this bought me the chance to restart the app while the aircraft was advancing very very slowly towards the homepoint.
After that it reconnected and I've managed to crank up the speed and successfully landed with about 23% battery left. This wasn't a close call by any means but I believe it could have been possible to lose the drone in this situation.
For example, if I didn't initiate the failsafe RTH from the controller, I believe the drone would have drifted away even further. I don't think it would have drifted away far enough to be out of signal range but it would have made returning back home harder with the remaining battery.
If it did drift away outside of signal range, I believe it would have been dead/gone by now. From what I've experienced so far, under windy conditions I've noticed that RTH doesn't work as expected. Once RTH is initiated, the aircraft tends to hover instead of speeding up the motors to the max in order to compensate the wind. Same goes for landing. I've noticed that once the aircraft is above the homepoint, it tries to stabilize itself instead of descending faster and it tries to constantly adjust it's position without descending or descending very slowly.
So moral of the story is: 3.1.8 tends to crash. Take that into account. All apps were closed on my Android device and it was also freshly restarted before the flight. Try to be a bit more conservative in order to accommodate an app restart. Even with the crashes, will I switch back to 3.1.23 and CE mode? Absolutely not. I believe the overall flight experience is way safer considering how good the signal was in FCC mode. I honestly believe I wouldn't have a drone today if I was flying in CE mode.
I will try to test 3.1.8 on iOS too sometimes to see if it crashes in the same way.
