The Aviary Effects API that helps developers create their own Instagram recently made the API public and updated its Developer Portal. In addition, the company is offering a short-term developer contest, so you'll need to get going quickly.
The Aviary API has been around for several years with embedable photo editors. It has the Feather API, allowing add inline photo editing tools to their web apps and the Suite API, giving developers an entire suite of image editing tools to add to their applications.
The Effects API is the third pillar in its impressive lineup of photo editing APIs. Unlike the other two APIs, the new offering is entirely behind the scenes instead of utilizing a customizable widget. You can filter photos through the Effects API, completely server-side.
Currently, the API has 18 filters for you to use in your app, including currently popular filters like the instant photo (Polaroid) and retro camera filters. Alongside the filters are some basic image editing "effects," such as cropping and resizing, as well as handier tools like red-eye removal and auto correction.
Finally, the API allows you to bulk process your photos, which is incredible.
If you're looking to play with the API a bit before you dive in to integrating it in to your app, the Aviary has included a Filter Sandbox that you can experiment with and see just how awesome this thing is.
And once you know what you want to build, be sure to check out the company's recently-launched developer contest. Submissions need to be in by May 24, with the winner getting an iPad 2. For ideas on what to build, check out our interview with Aviary's Michael Galpert at SXSW (embedded below).