Why are wallpapers sized at 480 pixels wide and 1600 pixels wide for mobile devices and desktops respectively?
480 pixels is the size of the screen width or height of most high-end phones out there today and many are actually smaller than that. If your phone screen is smaller, the image will automatically be sized down to fit. 1600 pixels is the horizontal resolution of many desktop displays (and many are still smaller). Your computer has settings for how to treat the wallpaper if the size of your screen does not match the size of the wallpaper. Unless your screen is significantly higher resolution than 1600 pixels across, you will have a great desktop wallpaper or screen saver photo.
