If you are flying a Mavic, or any UAS that uses a cell phone or table, find the setting that turns off Auto-Brightness, and crank up the brightness.
In my first test flight I discovered the need for a good sun shield. I invested in a good sun shield and that helped, but I have been struggling with ambient light making it difficult to see the screen. It just didn’t seem the sun screen was enough.
Yesterday the lighting was perfect, complete cloud cover and very bright. I couldn’t see much of anything on my iPad screen. During the night I realized the sun-shade must be blocking the light sensor. That would mean the brightness level would be way low and explain why the screen was so difficult to see. Today I confirmed that was my issue.
I would recommend turning off Auto-Brightness and cranking up the brightness before a flight, period. Add it to the list, select Airplane mode, set White Balance, Focus, etc.