Summary of Issue:
Mostly, failed to connect. Sometimes it said "Drone Connected", but then the screen froze and reacted to nothing. One time it actually started to go through the pre-flight checklist, and got green checkmarks on everything, but then immediately went into disconnected state (with disk icon in lower right, instead of "fly" icon). I deleted Dji Go 4 completely, and also Pix4D, in the course of trying different things. After about an hour and half at the site, powering everything on and off in every conceivable order, I gave up and called it a wasted day, started the loooong drive back home.
Date Issue Began:
Didn't word today (Jan 7). Worked fine in September-October 2017. Same drone, same phone. There has been an Android update since that time.
Mobile Device Model and OS version:
Samsung Galaxy S6 (Samsung-SM-G920V)
Android Version 7.0
Kernel version 3.10.61. dpi@SWDD5514 #1