Black Iphone Wallpaper Save Battery. If nothing else you should switch the wallpaper to plain black to save power on the lock screen and the home screen. This tool allows you to upload images and then transition the darker parts into true black.
This wont have a massive impact on battery life but if youre looking to squeeze every bit of juice from your battery. You can most likely see the place where something is going on. If you turn on Dark mode under Settings Display you could save around 30 percent of the battery charge according to one test.
It will save battery its a fact that it will need less power to drive the display even if infinitesimal.
To reduce the screen brightness open the Settings app go to Display Brightness or Brightness Wallpaper in iOS 7 and drag the Brightness slider to the left. Long-press the wallpaper and save it to your device. Here is an example of a smaller image with a gray background cropped for iPhone X and converted to true black using the app. Dark mode will not save you any battery power if youre using an LCD screen.