Here's what I think is awesome in this release:
Portrait Mask Support. If you have an iPhone running iOS 12 (and can take Portrait photos), Acorn will now detect the Portrait Matte from those images and turn it into a layer mask. The Portrait Matte is the image data which enables blurring in the background, or other fancy camera tricks. This means you can use this matte to erase and add fancy backgrounds or custom blurs for your image, all within Acorn.
Other Mask Features. You can now drag and drop masks from the layers list into another layer, or copy it out as a new layer. When exporting layers you now have an option to apply the mask on export, or just write it as an additional image along with everything else. There are a number of new shortcuts when dealing with layer masks as well.
Brush Stuff. If you're running MacOS 10.13 or later, you get a performance boost when brushing (painting, smudging, cloning, etc…). This is especially noticeable when brusing on deep color images.
I've also added options to the brush palette for adjusting flow, softness and blending. In addition to all this, there's a bunch of new brushes under the "Basic Round" category which are designed for the new brush engine.
Other Stuff. There's other good things including improved PDF export, various MacOS Mojave UI fixes, additional speed improvements with with deep images, and more. And as always, it's a free upgrade for anyone who has already purchased Acorn 6.