The cloud is a wonderful place, and it makes sense that developers are wanting to get in on the action, especially with Dropbox, which boasts over 100 million users so far. Finally, though, the company has announced the Sync API, which will allow developers to easily integrate their products with Dropbox without the developers having to do a lot of the work.
In the past, developers could integrate their services with Dropbox, but many of the abilities, such as syncing, would be the responsibility of the developer, meaning that Dropbox only supplied the storage at the time. However, Dropbox is bringing some of that to an end and will be transitioning some of the developers responsibilities onto itself.
Essentially, the Sync API allows other apps to just work with Dropbox, and it can even act as if Dropbox were a local filesystem on the device itself. The API takes care of syncing and caching, as well as retrying uploads and downloads, which gets rid of all the grunt work that developers had to go through in the past to achieve similar results.
The Sync API is available now from Dropbox's Developer webpage, and all the information you need to get started is right there. A few developers have actually already been using the new API in their apps, including Chris Cox, who is the developer of Squarespace Note. Cox notes that the new API cut his Dropbox code in half, which can also cut down loading times for the app.