I bought my Mavic Pro end of May, 2018. In the first 90 days of flying my Mavic I was plagued by DGI Go 4 issues involving constant disconnect. I read and watched everything I could find concerning DGI Go 4 and Android to find solutions. I did a lot of reading on the Litchi App and was very interested in the Waypoints mode that Litchi had. Far easier than DJI Go 4 App.
I discovered while flying Litchi Waypoints that I very seldom lost connection. At about 120 days into my flying, I finally abandoned DJI Go 4, flying it only rarely- and still having connection issues during the rare occasions of using DJI Go 4. I learned that DJI Go 4 is a "resource hog" compared to Litchi- in other words required a lot more of the phone's resources. Litchi, because it doesn't demand as much of my phone, works almost flawlessly. DJI Go has always left me in fear of losing the drone. I fly Litchi- been flying Litchi- for 5 months confidently!