Dexcom was one of the first companies to announce that it would have an Apple Watch app, and a recent FDA guideline made it clear that, as a secondary display device for a cleared CGM, the Apple Watch app wouldn't require its own clearance.

But users of other smartwatches, including the Pebble Watch and the Android devices have also had access to Dexcom CGM readings, just not through an officially sanctioned Dexcom product. A new Android watch app called NightWatch is one of the newest unofficial ways for Dexcom CGM users to access their data.

It builds on the work of the Nightscout project, a DIY open source project that caught the attention of the Wall Street Journal in a lengthy piece last fall. A group of engineers and developers built a platform in their spare time that allowed Dexcom G4 users to upload their data to the internet, and from there download it into a variety of devices. Because the technology was given away for free and not sold, the developers were able to avoid the FDA regulations that have slowed down the official development by Dexcom.

Meanwhile, Dexcom hasn't made any move to put a stop to the efforts, instead opting to play catch-up with their own official technology -- including the company's Apple Watch app.

As 9t05Google recently reported, NightWatch was uploaded about four months ago to Github. It allows Android Wear users to view data directly from Dexcom servers, from Nightscout or from X-Drip, the developer's own version of Nightscout. Users can check current CGM readings, view historical graphs, and even get alarm notifications, all from the watch app. That's the same basic functionality as the official Apple Watch app, but the Apple Watch version allows a user to track up to five users' glucose from a single app.

Given the recently simplified FDA pathway for secondary display devices, it may not be too long before Dexcom makes an official Android app available. Currently, Dexcom's FAQ on its website betrays the lengthy development process that company has to contend with. In response to a question about an Android app, the company writes "Dexcom Share is only compatible with select versions of the iPhone and iPod. The Bluetooth Low Energy technology required for our system was not available on Android devices when the Share system was being developed."