Dropbox has purchased Snapjoy in an alliance that will almost certainly be used to take on Facebook’s Instagram. Released for iPhone only in October, Snapjoy is a free service that organizes photos and makes them accessible anywhere.

According to a posting on the Snapjoy blog:

As a fellow Y Combinator company, we’ve always admired Dropbox and loved their product. From the moment we met the founders, it was clear we shared a common goal. By combining forces with their amazing team, we can leverage the technology and scale of their platform and focus on what matters — delivering an incredible photo experience to over 100 million people.

The mobile photo-sharing marketplace has seen significant changes in 2012. In addition to Facebook’s $1 billion purchase of Instagram, the year saw Google acquire Snapseed. Earlier this month, Twitter began promoting their own new photo-editing service.

Dropbox has yet to announce what changes they plan on implementing now that they own Snapjoy. As usual, we’ll keep you updated.