A few days ago I used TapFly for the first time. I didn't realize that the aircraft would not maintain its current altitude when I selected the point toward which it should travel. My unfamiliarity with the function resulted in an interesting section of flight. I'm glad that obstacle avoidance worked, at least enough to prevent a crash, despite the fact that the sun was setting and despite the fact that it was treetops which were being avoided. Yep, Clint, I was feeling lucky!