I use a second hand 7 inch Nexus (2012) mounted on a dedicated mount made by Brodit (£30 ish).
It is on very low profile ball mount that allows it to rotate through 360 deg from portrait to landscape and also tilts through about 15 degrees, which nicely allow adjustment to stop sun reflections.
It is excellent and through the industry standard four mount holes it fits onto an old Garmin pilot 3 yoke mount I had lying around so it nicely fits on the yoke.
I bought it online from a company called mobilefun dot co dot uk who have a massive range of Brodit and other products to fit all makes and models of tablets and an extremely rapid helpline to allow you to get the correct one (different Nexuses are different thicknesses.)
Certainly worth a look:
If I knew how to post photos on here I'd post a pic, but alas.....