You read a very personal mail on your iPhone in the train and your neighbor keeps staring into your phone. There is a solution, by adding a privacy screen protector to stick. But Apple has done in November 2009 even though a solution
patented. This is an iPod with an LCD screen with different privacy levels between which you can switch, but the technique would all mobile devices including Apple and the iPhone should work. The technique allows the user to the viewing angle of the unit to be set. In a privacy mode, the neighbor next to you have no chance to mail them to read.