I've tried several of these and this is the strongest I've found. Great quality and keeps my tablet in place without fear of accidentally falling out. Very impressed and would recommend.
MoKo Universal Laptop Stand Bundle - 4 Pack Anti-Slip Silicone Elevation Stand for Tablets, Laptops, and Keyboards - Gray
12 Review
Wacom Ergo Stand for Cintiq Pro 24: Optimize Your Digital Creativity and Comfort
14 Review
Mount ONKRON G100 silver
39 Review
27" Monitor LG 27UL500, 3840x2160, 60Hz, IPS, black/white
23 Review