When to go
Best time
Morning, Mid-day
From my knowledge, any month of the year is great to visit the Inland Sea; however, if you want more water "pools" within the dunes, then the locals recommended coming during the spring season when there has been a bit more rain to fill the area.
I went in April and during that time, there had not been much rain so the water within the dunes was either low or non-existent.
To have the best chance at capturing the brightest shades of blue, I always recommend shooting in the morning or midday when the sun is high above you.
Field tips
Before flying a drone, check and follow local drone regulations and permit requirements.
The Inland Sea (Khor Al Udaid) is a huge area and it can be time consuming to cover the grounds. It's an absolute must to bring extra batteries for your drone—and it also wouldn't hurt to have a car charger, too.
Getting enough height is important in terms of creating context for this image. If you're too low, it may be difficult to tell what you're looking at, and when you're a bit higher, you can conceptualize the landscape.
Don't focus on only one perspective while you're at this location. The water creates varying patterns in the sand, so every time you visit, it'll be slightly different. Be flexible and see what photos you can get with your drone.
Current weather
Do nearby
Get in the 4x4 and go driving around (dune bashing), hike the dunes to watch sunset or just relax and enjoy the tranquillity of the Inland Sea. I went down to the area for a little swim to cool off—it was so nice!