image-open-logic-blog-nightscout
November 19, 2019

Diabetic? A Dexcom App Option Is Available for Android Via Nightscout OSS

Monitoring
Open Source

How can diabetics and their families access data from Dexcom continuous glucose monitoring devices using their Android devices? And how does the open source project, Nightscout, help? Read on to find out.

What Is Dexcom and Continuous Glucose Monitoring?

Dexcom is a manufacturer of leading continuous glucose monitoring (CGM) devices that diabetics wear to get continuous insight into their blood glucose levels. There are Dexcom apps available for iOS devices that provide another avenue for viewing a user’s glucose data — and receiving alerts. Unfortunately, there is no Dexcom CGM app for Android. And the other CGM manufacturers only provide iOS apps for their devices as well. 

Nightscout: The Open Source, Cloud-Based Dexcom App Option for Android

To give Android users the ability to view their CGM data, the open source community created Nightscout. It is an open source, Dexcom-app option for Android-device users. However, Nightscout works with other CGM devices as well. 

For more information about the birth of the Nightscout community, read my blog, Nightscout, Open Source, and the Diabetic Community

If you are unfamiliar with open source technologies, read the blog, What Is Open Source Software (OSS)? 

Deploying Nightscout: The Dexcom App Option for Android Device Users

I’m going to walk you through how to setup a Nightscout website using free cloud services.

Step 1: Review Nightscout Documentation

I wrote this blog to provide quick and clear instructions for setting up a Nightscout website. However, review the Nightscout documentation, including the warnings, here, to get a more in-depth understanding of the technology.

Nightscout color codes its official documentation based on which monitoring hardware you use. For example, green is for Dexcom and purple is for MiniMed. Other third parties have their own document section, here

Step 2: Create a Nightscout Web Monitor Instance in GitHub

To create your Nightscout web monitor instance: 

  1. Create a free-plan GitHub account.
  2. Fork the Nightscout Web Monitor GitHub repository to your GitHub account. 
  3. Using a laptop or desktop, configure your Nightscout instance, including the alerts it will send you, in ml/dl. The parameters you need to set include: API_SECRET,BG_HIGH, BG_LOW, BG_TARGET_TOP, and BG_TARGET_BOTTOM.
  4. Configure your preference of Dexcom Share Bridge or MiniMed Connect bridge. 

Step 3: Configure a Cloud Service to Connect With Your Nightscout Web Monitor Instance 

You have your choice of two cloud services to use with Nightscout: Heroku and Azure. 
I created these instructions to use Heroku because it will run 24/7/365 — and it’s free. 

To set up Heroku to connect with your Nightscout web monitor instance: 

  1. Create a Heroku account. Heroku will ask for your credit card when you are setting up your account, but it will not be charged unless you authorize a paid account.
  2. Go back to your Nightscout repository in GitHub. On the main Nightscout Web Monitor screen, click the purple button labeled, Deploy to Heroku.

Now you can access your Nightscout site via Heroku.

Step 4: Create an Automated Process to Ping Your CGM Device for New Data

To automatically monitor your CGM device and upload new readings to your Nightscout website, create an Uptimerobot. It is an “automated bot technology” that will ping up to 50 devices every five minutes for you — for free. 

To deploy an Uptimerobot:  

  1. Go to https://uptimerobot.com and create a free plan.
  2. After you set up your profile, click Add New Monitor.
  3. Select HTTP(s) for the type. Using HTTPS implements the security needed to protect your data.
  4. Paste in the URL for your Heroku instance. 
  5. Check the settings of your Dexcom app. You may need to turn sharing to active and add at least one user to get the UptimeRobot working properly. 

Step 5: Add Monitors to Your Nightscout Website 

Dexcom apps give users critical insights from their data, including alarms about a person's glucose levels. You can do the same with Nightscout site by taking advantage of other open source tools. 

The developers over at Logz.io have made free monitoring tools using the Elastic (ELK) stack. However, the offerings are designed to support commercial-level deployments. Another option is to set up a monitor for your CGM app and Heroku instance using the MongoDB and Node.js open source technologies. For complete deployment instructions, go to predic8 GitHub

The monitors that you can set up with the help of ready-to-go tools in predic8 will enable you to ingest, analyze, store, and display data that is sent from your Dexcom app to your Nightscout website. For example, you can:

  • Set alarms that Android users can receive that flag when a person's glucose levels are dangerously high or low.  
  • Create different dashboard views of your data that are easy to view with your Android device. 
  • Take advantage of plugins to monitor your Dexcom device’s battery life, time intervals between checks, and meal trackers.

There are many other options that you configure, so I highly recommend checking out the project over at https://github.com/predic8/cgm-remote-monitor

Open Source Provides Critical Options — to People and Organizations

Hopefully, one day, the Android-using diabetics of the world will be able to enjoy the same choices as their iOS brethren. Until then, we are lucky to have volunteers in the community who work tirelessly to better the lives of those around them — and give people technology options by providing solutions such as Nightscout.

In addition, there are thousands of open source communities that develop and maintain free technologies that make it possible for individuals and global organizations to innovate faster and for less money. Many of these free and open source solutions are just as powerful, secure, and reliable as expensive commercial options that often dictate the platforms that people need to use. 

OpenLogic helps organizations take advantage of open source software by providing services including mission-critical support for hundreds of open source technologies. For example, OpenJDK is the free and open source equivalent of OracleJDK, which involves a paid license. Earlier this year, Oracle unexpectedly increased the cost of OracleJDK, creating issues for many companies. OpenLogic helps organizations take advantage of open source software for enterprise solutions such as OpenJDK, by providing services including mission-critical support.

If you use OracleJDK, read the Forrester report about OpenJDK to learn why open source technologies are important to consider.

READ Forrester REPORT