When you open up a photo taken with an iPhone that offers Portrait Mode, Pixelmator Pro will open the photo itself along with a useful layer mask for doing things like swapping out the background in just a few minutes.
The portrait mask uses the depth information from the iPhone to isolate the subject of a photo, making it easy to remove background elements with little effort.
The Portrait mask feature is limited to the Pixelmator Pro software, and it is not available on the standard version of Pixelmator or the Pixelmator app for iOS devices.
Pixelmator Pro has been around since late 2017 and it has seen several major updates since then with the Pixelmator team introducing useful new functionality on a regular basis. Pixelmator Pro can be downloaded from the Mac App Store for $39.99, and there is a free trial available on the Pixelmator website. [Direct Link]