Acorn
Acorn is a Mac-only direct competitor to Photoshop. Acorn features numerous advanced editing features such as layering, image effects, filters, text effects, and vector tools. Acorn 6, the latest release, adds new features like image metadata manipulation, layer export sizing, and cloning across images and layers. Acorn can import images from your camera, the web, or even Photoshop. Acorn can be bought for a flat price of $29.99 directly from the developer’s website or on the Mac App Store. However, the two versions are slightly different–the one from the website includes a few extra perks such as faster updates and the ability to write your own plugins. Older versions of Acorn can be downloaded for free off the website.