Change wallpaper when device screen is locked: - This feature is available in both Nice Wallpaper 4K. The background will be changed when the user locks the device. Although the user must be on the Home screen for this feature to activate. - Abstract, Animals, Birds, Anime, Cartoon, AMOLED, Art, Celebrities, Fantasy, Airplanes, Planes,, Sand, Forest, Trees, Women, Men, Boys, Girls, Technology, Sports, Holidays (Christmas, Santa Claus), Musical Instruments, Vector, CUTIE / KAWAII, Minimalist, no