I will just post this as a FWIW and general information so it has it's own thread. I bought Litchi for Android several months ago and have wasted enough time to buy a P4 trying to get it to work. Believe me I am not cheap as I have tried it on an LG Stylo, a Galaxy Note 4 and two Galaxy Tab S LTE tablets. NoGo after hours of fiddleforking around with unknown sources, usb debugging, etc. etc. I discovered Ultimate Flight during my frustrating attempts to get this working, and bought it. Installed it--- turned it on, went through a bit of setup after a cursory read of the manual and VIOLA. Worked the first time out of the box. SAME fripping Tablet as I had been trying for months. Un--Flipping--Believable. Now I have only flown a half dozen missions so far, but it has been flawless. This ordeal with Litchi had really soured me on non-DJI software, but UF undid that. The user manual is professionally written and about 90 or 100 pages. I haven't needed to contact the dev yet so I can not comment on that, but thus far I am more than pleased. I have not read any reports here of flyaways with UF either, as that was one thing which encouraged me to give up on Litchi. That is just my experience, for what it is worth. I hope this does not hurt any of the Litchi aficionadoes feelings, I am just the reporter.