I think the UI is cleaner and more Mac-like; Pixelmator felt a little too comfortable throwing consistency and OS X UI standards out the window. It&#x27;s been a while since I tried Pixelmator, though, so maybe this comparison is no longer fair.<p>Also, though it probably won&#x27;t matter for most people, Acorn&#x27;s file format is pretty ingenious: <a href="http:&#x2F;&#x2F;shapeof.com&#x2F;archives&#x2F;2013&#x2F;4&#x2F;we_need_a_standard_layered_image_format.html" rel="nofollow">http:&#x2F;&#x2F;shapeof.com&#x2F;archives&#x2F;2013&#x2F;4&#x2F;we_need_a_standard_layere...</a>