Spray the screen’s area with water to dissolve any stubborn particles, like dried milk spills, before you start cleaning. Isopropyl alcohol: Dampening your cloth or cotton swab with water will often do the trick, but alcohol is a really effective cleaner. This Max Skilled spray ($13) is simple to use. https://martinojbsh.blogsidea.com/32457980/the-basic-principles-of-best-iphone-cleaning-kit