Action Launcher has garnered a fair bit of praise from us at Android Central. Some love Quickdrawer and being able to ditch the traditional app drawer. Some love the Covers and Shades, which free up space and get us into apps faster. But as a themer, Action Launcher's got a great trick that can make your home screen feel completely new with one easy step.
Setting a new wallpaper in other launchers just gives you a new image behind all your widgets and folders. Setting a new wallpaper in Action Launcher will change not only that image but will recolor your Quickbar, Quickdrawer, and folders. Quicktheme does this by sampling colors from your wallpaper and using them to color the launcher's other elements in colors it believes it'll match. That beats digging around in Nova Launcher's settings to re-color everything manually. You can even choose between several tints for your themes, most are pulled from your wallpaper but there will always be two defaults: Material Light and Material Dark.
During Action Launcher's most recent overhaul, Quicktheme got a handy little upgrade. Colors were arranged in a grid rather than a list, allowing you to better compare your choices, and Quicktheme finally got transparency support for the Quickbar, Quickdrawer, Quickpage, and dock and folder backgrounds. This has made it easier and quicker to get the hue and shading you're after, then get back to your busy day.
In most instances the algorithm Action Launcher uses to pick these shades will be enough. For wallpapers with a lot of colors, or wallpapers with a very small amount of an accent color you're trying to match, it can sometimes miss. Sadly, the only way to draw new colors is to set the wallpaper again with a different zoom or crop. There are also instances when Action Launcher fails to pull colors from a wallpaper altogether, as it samples colors from a live wallpaper's icon rather than the live wallpaper itself.
While the ability to manually set colors when the pre-selected colors fail would be great, the built-in tones work well for most wallpapers and themes. Being able to simply set your wallpaper and watch the rest of your launcher re-theme itself to match is gratifying, instead of having to fuss around in your launcher's settings manually re-coloring your folders and drawers.
Updated September 2017: Updated for Action Launcher's new-old name and its updated Quicktheme features and UI.