I mentioned this in another thread but it bears repeating. They've changed something about the glass between the 4 and 4S. With my polarized sunglasses and a Power Support Anti Glare HD film, the iPhone 4 looked the same at any angle. With the same glasses and same screen protector, the 4S has a terrible blue-green tint in the vertical position, with pink and yellow diagonal streaks. It's somewhat lessened in landscape, but there's a magenta cast. The screen looks ok only when held at a 40 degree angle. And the worst part is that it looks better overall (but still discolored) with NO screen protector.