[How to set a wallpaper on iPhone 6s]
Hold down on the COSMO DARTS wallpaper and the option “save image” comes up.
Save the image and go to “settings”. Tap on to open the “settings” and choose “wallpaper”.
Select the COSMO DARTS wallpaper which you already saved and tap “set”.
(After you choose a wallpaper, you might need to move or scale it to fit your screen.)