OLEDBuddy

Images with true blacks are great for OLED (including AMOLED) screens, as those pixels are actually off! This gives slightly better battery life, and brilliantly inky blacks. With OLEDBuddy, you can easily open an image, view which pixels are true black, what percentage of all pixels are true black, and if necessary, easily convert lower valued pixels to true black. The conversion is tunable by simply tapping the image to choose a threshold pixel, or by using three sliders, to control the threshold for Red, Green, and Blue values that will get dropped to 0, and a live preview is shown before choosing to save. Once saved, you can easily open, share, and set as wallpaper from the notification. This app was developed with the community of /r/amoledbackgrounds in mind.