wow, some pretty pedantic people around the forums
me personally i wipe the screen with a tissue or my shirt sleeve when i notice smudges are getting in the way of reading, and that's pretty much it. that might sound slightly careless but ive honestly never had a scrape on any of my technical devices and that without the aid from screen protectors and the like. (minus of course, the ipod classics back, though that scratches up even with a cover, for the most part).