What are some alternatives?
When comparing Pixelmator and Adobe Photoshop, you can also consider the following products
GIMP - GIMP is a multiplatform photo manipulation tool.
Affinity Photo - Affinity is the imaging and design suite for creative professionals exclusively for Mac.
Krita - Krita is a professional FREE and open source painting program. It is made by artists that want to seaffordable art tools for everyone. Concept art. texture and matte painters, illustrations and comics.
Pixlr - Pixlr® makes it easy to transform everyday images into stunning works of art.
Sketch - Professional digital design for Mac.
Canva - Canva makes design simple for everyone. Create designs for Web or print: blog graphics, presentations, Facebook covers, flyers, posters, invitations and so much more.