i can report that panasonic fisheye works. i just stick 1-2 coins with velcro at the back. you could improve at bit by stick a small coin at the side but its minimal.
quality is good and defish ok. give you the widest image you can have.
i planned to do the same.
saw the report saying samsung 10.1 with dimension of 243.1 x 171.4 x 7.3 mm works.
I guess we can trim the foam 1-2mm each side and it should fit