I recently bought the Lifeproof Nuud case for my iPhone 5s. The screen has got pretty dusty and I’d like to clean it. What’s the best way to do this? Kate Lesou The Nuud case (lifeproof.com) seals the iPhone with a back shell that wraps around to cover the edge of the screen where the glass meets the bezel. This leaves the touchscreen free, but still keeps the water out. If you get dust or dirt on it, you can usually just rinse it under the tap. If you’re concerned there might be dirt caught in the seal, just open it up, brush the phone clean and carefully clean around the rubber o-ring of the case.