A glucose monitoring app defect (Z-2163-2026) — low-priority work blocking high-priority work delays what is displayed
A smartphone app for a continuous glucose monitoring system recalled for a software defect in which a low-priority file check blocks the higher-priority thread processing glucose values. Specific app versions are in scope, covering 58,582.
Recall overview (primary data)
- ClassificationClass II
- Product typeMedical Device
- Recalling firmDexcom, Inc.
- ReasonA software defect in which a low-priority file I/O check blocks the higher-priority thread responsible for processing estimated glucose values (EGVs) and trend arrows. When the app is running in the background, EGV notifications may queue up and then "replay" sequentially when the user brings the app to the foreground, causing the Glucose Compass to flicker through previous EGVs. In more severe instances, the app may perceive signal loss and deploy signal loss mitigations. This delay in EGV and alert processing creates a risk that users may miss detection of a hypoglycemic or hyperglycemic event, or make treatment decisions based on outdated glucose information.
- DistributionSW12300 & SW13355 Dexcom G7 iOS and watchOS app versions 2.9.0 through 2.11.2: Worldwide - US Nationwide including in the states of AK, AL, AR, AZ, CA, CO, CT, DC, DE, FL, GA, HI, IA, ID, IL, IN, KS,...
- Recall initiated2026-04-14
Key points
- A smartphone app for a continuous glucose monitoring system was recalled for a software defect.
- A low-priority file input and output check blocks the higher-priority processing of values and trends.
- With the app in the background, notifications queue and replay in sequence when it returns to the foreground.
- Scope is stated as app versions 2.9.0 through 2.11.2, the role manufacturing lots play for physical goods.
- The classification is Class II, the quantity 58,582, and distribution spans the United States and many other countries.
1What is recalled is an app
What this record covers is not a physical instrument but specific versions of a smartphone application. Software forming part of a medical device falls within the scope of a recall. The records this site holds include several recalls for software defects.
That scope is stated as versions 2.9.0 through 2.11.2 follows from that difference. For physical goods, manufacturing lots set the range; for software, versions play the same role.
2What happens
- 1The mechanismA low-priority file input and output check runs
- 2The effectThe higher-priority processing of values and trends is blocked
- 3With the app in the backgroundNotifications of values queue up
- 4On returning to the foregroundQueued notifications replay in sequence, showing previous values in turn
The defect arises from how processing priorities were assigned. Where processing values should take precedence, a lower-priority check leaves it waiting. The result is a period in which the value a user sees is not the current one.
3What glucose monitoring is for
Continuous glucose monitoring exists so that responses can be judged from how values move. Where the value displayed is not the current one, the basis of that judgment changes. The classification is Class II, the category carrying a possibility of temporary or medically reversible harm.
4Software becoming a device
An app that displays measured values is itself regulated as part of a medical device. This site also covers device classification and the submission routes separately. Something with no physical existence is treated as a device, its scope fixed by version number and its remedy delivered as an update. What the word recall actually involves differs greatly with what it covers.
Why it matters
Where software is regulated as part of a device, scope is set by version and remedy is delivered by update. Because older versions persist until users update, how far notice reaches determines whether the remedy takes effect.
FAQ
Can an app be recalled?
How does it differ from a physical recall?
Sources (primary)
Source: openFDA (U.S. FDA, CC0 public domain). Data is provided as-is and must not be used for medical decisions. Verify the latest and exact details with the official FDA recall information. This site is not endorsed or certified by the U.S. FDA.
- FDA recall information (official)
- openFDA (data provider)
- Recall number: Z-2163-2026