We're interested in tracking the ways that photographs (and photography books) are appearing on digital devices. For better or worse, there are any number of possibilities for displaying photographs on screens. Last week, independent photography book publisher Hassla released an iPhone app which enables their fans to keep track of new releases, preview book content, and find physical locations to purchase books. Sure, it's not a new idea for a company to put out an app, but a small photobook publisher? It may be the first one to surface so far.