Flying Meat has Acorn 4 for the Mac in the Mac App Store or The Flying Meat Store for $14.99 (regularly $49.99) for a limited time.

Acorn is an easy to use yet powerful picture and image editor for the Mac (OS X 10.8 and up). Add text and shapes to your digital pictures. Combine images together to create a photo collage. Work with layers to touch up your favorite photos or make something entirely new from scratch. It’s easily my go to image editor and the one I recommend.