A while ago a build a hood for an Ipad mini. It did worked but only a little bit. In full sunshine I could barely see the screen. So I decided to make a makeshift viewer. I bought two +3 reading glasses (wall-mart type) and built them in a holder made of cardboard and lots of gaffer tape. And some pieces of velcro. In my backyard with full sunshine it worked very nicely. I will do some more practice tests and if it turns out well I will make a more decent model.