To test out a color, just tap a section of the wall in question from a photo on your device, and — using proprietary algorithms that employ edge detection and color analysis — it will take into account its full swath. Next mix a custom paint blend from their color wheel, or choose from preloaded brand-specific fan decks, and let it work its color-changing magic. It will even take note of the original color it's going on top of and subtle lighting differences in the room, so you know exactly what you're getting yourself into.
Joe McGauley is a senior editor at Supercompressor. His arms are very thankful this app exists.