Dexcom launches public API for third-party apps to leverage retrospective CGM data; major win for driving diabetes app ecosystem – September 20, 2017

Executive Highlights

  • Dexcom launched its public API yesterday, allowing third-party software developers to register at and build novel retrospective CGM data apps. 
  • Partners One Drop, Tidepool, Nutrino (food), App Practice (physician monitoring), Rimidi (population management), Achievement (rewards), Ensa (supplement recommendations), and Evidation are already integrating the API into their apps.
  • Dexcom users will be able to authorize which apps can access their CGM data, enabling patient choice. Like Dexcom Clarity, this platform remains a Class I device. Dexcom will provide significant support for developers, reflecting a huge internal investment.
  • Third-party developers will have access to quite a bit of information to develop novel retrospective CGM data apps, including glucose data, statistics, device info, and calibrations. These are industry standard “OAuth2” and “RESTful APIs.”
  • The bold move is intended to drive an ecosystem of creative CGM data displays/apps. Dexcom recognizes it cannot (and should not) build all useful CGM software internally. This could serve as a competitive advantage for Dexcom, assuming an app ecosystem takes off and patients/HCPs/payers derive meaningful value from it.

Yesterday, Dexcom announced the launch of its public API for retrospective CGM data (three-hour delay). The goal is to “Fuel Diabetes App Innovation” by harnessing the creativity of the developer community – pulling a page out of the books of Google, Apple, and many others.

At, third-party software developers in the US can now register with Dexcom, access the API, create and manage their own novel retrospective CGM data apps, play with simulated (sandbox) data, and submit an app to Dexcom for commercial review. The site has been built out with great examples, documentation, FAQs, and a whole support system – wow is this a serious investment from Dexcom, reflecting over a year of internal development.

Data partners One Drop, Tidepool, Nutrino (food), App Practice (physician monitoring), Rimidi (population management), Achievement (rewards), Ensa (supplement recommendations), and Evidation are “already accessing the API for patient-approved CGM data retrieval” – see the App Gallery here and pictures below. Dexcom’s press release quotes One Drop CEO Jeff Dachis and App Practice founder/endocrinologist Dr. Rakesh Patel.  A few examples of what is possible:

  • Patients can explore how their food choices impact their glucose (Nutrino), connect to coaches and diabetes peers in a data-driven community (One Drop), and receive insights combining data from other devices, medical records, and apps.
  • For HCPs, App Practice and Rimidi allow clinicians to view patients’ CGM data on their smartphones, integrating into mobile patient care and billing workflows. This could be a huge driver of population management and new, continuous models of care.

We are especially big fans of the approach Nutrino is taking with food; Achievement’s use of rewards; and the population health potential of Rimidi and App Practice. The One Drop and Tidepool integrations are not different from what we’ve seen previously, though as “official” partners perhaps there will be even more investment. This API does not replace Apple Health integration, which is still available for sharing CGM data between iOS apps.

Third-party developers will have access to quite a bit of information to develop novel retrospective CGM data apps, including glucose data, statistics, device info, and calibrations. These are “OAuth2” and “RESTful APIs” – exactly what open data proponents like Tidepool’s Howard Look have desired for years. Like Dexcom’s own Clarity software, apps using the API are a class I device (retrospective CGM data). Dexcom will support data partners and share best practices through the developer portal.

With this news, Dexcom continues to drive the broadest partnership strategy in CGM, understanding that it cannot (and should not) build all the useful CGM data apps. We’re elated to see it enabling an app developer ecosystem that could propel others to use CGM data “to enable new solutions and business models.” Will Medtronic and Abbott follow Dexcom’s trailblazing lead?

  • Patients will have control over what apps can access their CGM data and can revoke access at any time, in line with Dexcom’s belief in “in data mobility and customer choice.” Nice! Presumably this will work like other OAuth2 approaches (e.g., “authorize Twitter”), meaning people with diabetes would sign in and authorize the data sharing between Dexcom and the third-party app.
  • Signing up as a registered developer is simple (no review process!) and allows limited access to sandbox data. Before launching apps, developers must apply for “full access” and sign a data partner agreement with Dexcom – see the “Scopes & Access” page. We’re not sure of the revenue sharing implications, though presumably this varies by partner. Partners will not be able to leverage Dexcom’s quality systems, as we would expect.
  • This bold move has been more than a year in the making, as Dexcom’s SVP of Data Annika Jimenez first shared API plans at last fall’s Diabetes Mine D-Data Exchange. The launch comes later than the initial goal for “early 2017,” but comes on the earlier side of the updated ADA plan to launch “later this year.” Dexcom’s Director of Data Partnerships Dr. Nate Heintzman (the Great) shared in June that 500+ people had signed up for email updates on We imagine interest has only grown since that time.

Close Concerns’ Questions

Q: Will Dexcom’s APIs emerge as a significant competitive advantage?

Q: What third-party retrospective CGM apps will be most useful? What fraction of Dexcom’s users will take advantage of these apps? What fraction of Dexcom users currently use Clarity at least once per month?

Q: How will insulin delivery data fit in, once smart pens/caps are available?

Q: What are the payer and business model implications of Dexcom’s APIs? What will this look like in two years, particularly if Dexcom launches its own decision support?

Q: Will Medtronic and Abbott follow with their own APIs?

Q: What was the hardest part of launching this?

Third-Party App Examples Using Dexcom CGM Data


“Discover your individual response to different foods so that you can maintain a healthy diet.” As a reminder, Medtronic is also partnered with Nutrino, including in the IBM Watson-powered Sugar.IQ app.


“Achievement is a tool that allows users to earn rewards for healthy actions.”

App Practice

“App Practice enables patients to tackle all stages of diabetes—from pre-diabetes onward—using our clinically-tested, social iOS apps. For physicians who are tired of the status quo, App Practice enables better and faster care while increasing patient satisfaction and reducing clinical costs. Physicians can monitor the progress of patients that use the apps to better manage patient health.”


“Rimidi's clinical management platform marries patient generated data, including BGM and CGM, with clinical data from the EMR into a streamlined user experience optimized for workflow efficiency. Clinicians monitor key quality measures, triage patient needs, and identify specific gaps in care. Our unique predictive analytics allow clinicians to visualize the anticipated impact of treatment decisions on patient outcomes. Patients get timely feedback and better insight into their care.”


One Drop Mobile

One Drop Mobile is a cloud-based diabetes management solution available on iOS and Android. Track blood glucose, food, medication, and activity data; get real-time insights and detailed blood glucose analytics; share reports with your healthcare team; and interact with a worldwide community of people with diabetes.


“Tidepool is free, nonprofit software that liberates data from pumps, BGMs and CGMs and lets you see it all together in one place on the web or your phone.”


“Sync your health history + biometric sensors (Apple Watch, Dexcom CGM) and receive curated wellness + supplement recommendations.”

Dexcom Data Partner Process Overview

  • Dexcom partners will have access to retrospective data APIs initially (three hours old), but we hope the delay could be reduced over time in negotiation with the FDA (perhaps to two hours or even one hour). We would note that the unauthorized DIY automated insulin delivery app, Loop, posts Dexcom CGM data to Apple Health immediately (it requires the transmitter serial number to be inputted directly into Loop). Obviously Dexcom cannot endorse this, but it does show it is possible. As we understand it, the nuance here concerns when CGM data crosses from class I (retrospective) to class III (real-time). As the gap narrows, Dexcom’s liability and regulatory burden presumably increases.
  • Ms. Jimenez has significant Big Data experience from Silicon Valley (she spent years at Yahoo!), and noted last year that Dexcom has always been open to partnering on the data front. This move to expose its APIs sets a new standard for the field. Last year, Ms. Jimenez shared several examples like Amazon, Apple, Google, GE, and Uber, noting that “a data platform simplifies our experience and raises the bar on what’s possible.”

-- by Adam Brown and Kelly Close