The first thing you’ll notice with Pixelmator is it’s distinctively chic, black, semi-transparent graphical user interface. Its frames and floating windows is built around black containers making your images pop - allowing your eyes to focus on the image you are editing and takes away the visual clutter that may disturb your vision on screen.

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One thing unique about Pixelmator is its smart palette hiding feature. This feature hides unnecessary frames from view while a tool is currently in use. Standard palettes come back to view once done. So when, for example, you are currently adjusting an image’s saturation, all unnecessary floating palettes dissolve from view leaving only the image and the saturation slider window. As a result, visual clutter is reduced, allowing you to focus on the editing controls you are currently engaged in.
Pixelmator also provides this small but much appreciated notification feature that pops up every time you undo or redo an action. For example, you want to undo a gradient you just applied, hitting on Command+Z will undo the last action and pop up a message “Undo Gradient” on the image you are working on, making it easy for digital artists to back or forward track properly.
Amazingly enough, Pixelmator is both powerful and lightweight. It doesn’t take as much time to load compared to Photoshop, and works without making you feel like your system is bogged down.