Most of us want a bigger screen for the phone, but of course that cannot come at the cost of mobility. So the screen size of any mobile device is limited by definition. Though we don’t have to worry about these things much with technology keeping pace with such issues.
A very simple solution to the large screen problem would be to have a pico projector built-into mobile phones, but then we don’t really want those power hungry projectors sucking up all the juice from the phone. Which means the wisest solution for the present be something much like the Monolith case for the iPhone.
Built for the iPhone 4/ 4S, the case includes its very own projector to work with the iPhone, and project images on nearly every flat surface. Plus, it has its own battery so it won’t suck the life out of the iPhone. Priced at ~$260.