Photo Filter App UI

I found myself wishing for an photo editing app with a filter to achieve the gradient map effect used so effectively by Spotify and others recently. Got me curious how to translate a UI that needs a mouse to a touchscreen. Decided to pop open Sketch and try to figure it out.

Photo courtesy of Benjamin Combs via Unsplash (https://unsplash.com/photos/hiAdjnXZxl8)