Speaking of Dropbox, the company had its first developer conference last week, where the company announced its Dropbox Platform, consisting of a Sync API, a number of ‘Drop-ins’, and a Datastore API. The platform builds on Dropbox’s Core API, which was released in late 2011 and which enables apps that use that API to store and sync files across devices for Dropbox users. The latest announced features take sync’ing beyond files, allowing web (javascript) and mobile (iOS and Android) apps to use the Datastore API to sync underlying app-related structured data (say the state of an in-progress mobile game, or an app-configuration, or key strokes that go into a digital drawing) across devices for a Dropbox user.

Dropbox’s freemium business model has seen a free-to-paid conversion rate of approx. 4%. Assuming that conversion rate stays reasonably stable, growth in its current user base of 175 million will be a key business driver for Dropbox. The interesting piece is that while there are a few billion individuals with multiple internet-connected devices (thus Dropbox’s user base being a small piece of the pie), very few pure-play networks have been able to grow larger than where Dropbox is today. So how do you tackle the growth challenges at such an inflection point? You develop an ecosystem of apps that use the Datastore API to simplify their development efforts around sync’ing, you use these apps as channels to reach new devices, you thereby obtain more Dropbox users, and soon you have created a positive feedback loop for additional virality. This is an interesting case where the app piece and the platform / middleware piece complement each other very well. So even if Dropbox makes not a single dime off the app-developers that use its Datastore API, there should be enough value for the company to make this all worth the effort.