I have been having a little fun with a very cheap accessories I bought at Typo (yes the stationary and scrapbooking accessories place). Its a simple clip on design and the lens just sits over the small camera lens. It works fine on both my Android phone and my HP Spectre (a tablet laptop cross over) although there is some vignetting at the edges.
As a wide angle of a distant screen it is fine, but I’m not really a fan of the fish eye effect on a landscape. However letting it get right upclose (the macro aspect) definitely gives a different, aka interesting, perspective of some familiar items around my studio