There are a lot of mobile, desktop and helper apps tied to Flickr. The team at the photo sharing service decided to make those apps easier to find and install by opening a free "App Garden" to everyone.
Like you might expect, the App Garden is an uncluttered, keen-looking showcase for the efforts of Flickr-happy developers and companies that have made it easy to download and upload photos to the service from many platforms. Apps are tagged by developers, making it fairly easy to find, say, a desktop Mac uploader or Android-based tool.
To help users stumble across great apps, Flickr has also started tagging photos with the tools they were uploaded with and a link back to that app in the Garden. Share some of your favourite Flickr app finds in the comments, and read up on Flickr's API if you're interested in developing an app yourself.