Review on Secure and Portable Universal Tablet Hand Strap Holder by Fintie: 360 Degrees Swivel PU Leather Handle Grip with Elastic Belt for iPad/iPad Pro and 9-10 Inch Tablets - Black by Thomas Chalecki

Such a simple thing but solved my problems perfectly. The loops fit 2 opposite corners of the tablet and it has an elastic band that keeps it secure but also allows for the use of tablets of different sizes. The wrist strap is rotatable, so you can use it comfortably whether you are left-handed or right-handed and whether you hold your tablet vertically or horizontally. I wish I had had it many years ago!