I'm sure all of you experienced pilots know this, but I just found it out and thought I'd post it anyway. I have a P3S with an Android tablet. Mine works very well. No problems. Been flying it for about 3 weeks now. Yesterday, my cousin in northern California bought one. So naturally he calls me for advice. I helped him assemble it, download the app, and then do the required update. When we finished, the controller would not connect to the drone. We finally figured out that we had to re-link the controller to the drone. The procedure is on page 24 of the manual. Getting the manual is a must! I didn't even know that little push-button existed until I read about it in the manual. Next, he could not get the motors to turn on for indoor testing. The problem was that he lives in a Mobil home, surrounded by metal. No GPS signal! And the drone was in "Beginner Mode". As soon as he took the drone to an open field, he got tons of satellites, and then the motors turned on by stick command. Apparently, you can not fly the drone without satellites while in beginner mode. Bottom line, all is well now. And it sure helps to have, and read, the manual.