Just like Pixlr's web version, the desktop edition offers all the basic tools for easily cropping and resizing your images, as well as stylized filters to turn your photos into sketches and watercolors. Signing up with a free account with Autodesk will also give you access to additional effects, overlays and double exposure to create more advanced edits. You can also pay $2 a month or $15 a year for advanced tools like Influence Masks for stylized text. Pro members will also get additional features over time.
If you're a heavy Photoshop user, you won't be able to jump ship; Pixlr's aimed more at the person who just needs low-level tools. Even the Pro version of Pixlr pales in comparison in terms of feature set. But if you're someone who just needs to crop, resize, and throw the occasional overlay on there, it's one of the best free alternatives.