Privacy policy

Last updated 15 September 2026 · Applies to the AfterSpike app for iPhone, Apple Watch and Garmin, and to afterspike.com

AfterSpike is built so that your glucose data stays with you. This page says exactly what the app reads, where it keeps things, and what leaves your phone. The short version: there is no AfterSpike server, we do not see your readings, and we do not track you.

What the app works with

Glucose readings

Readings can come from three places, and you choose which:

• A directly connected sensor. The app talks to the sensor over Bluetooth on your phone. The connection is between the sensor and your phone only; no cloud service sits in between. To do this the app stores the sensor's pairing details in the iPhone's Keychain, on the device.
• Apple Health. With your permission, the app reads blood glucose samples that other apps and meters have written to Health, and writes the readings it collects back to Health so your history is complete across devices. You control both directions in the Health app, and can turn either off at any time.
• Readings you type in. Kept on your phone and, if you allow Health writing, saved to Health marked as entered by you.

What you log

Meals, insulin, medication, exercise, water, stress and notes you add, including insulin units when you give them, are stored on your phone. If you are signed in to iCloud, they also sync to your private iCloud database so they follow you between your own devices. That database belongs to your Apple ID; AfterSpike cannot read it, and Apple handles it under Apple's own privacy terms.

What the coach decides

The coach keeps a short log of what it said and why, on the phone, so you can read it back in the app. It also keeps summary statistics it computes from your readings and your logs (for example how long it usually takes you to get back into range after a walk). All of this stays on the phone.

What never leaves your phone

• The coach runs on Apple's on-device model (Apple Intelligence). Your readings and logs are not sent to any server to be analysed, by us or by anyone else.
• There is no analytics or advertising software in the app, and no trackers on this website. We do not know who uses the app or how.
• We have no account system. The app never asks for your name, email address or any identifier.

Watches

If you use the Apple Watch app or complications, readings travel from your iPhone to your watch through Apple's own device-to-device channel. If you use the Garmin integration, readings travel from your iPhone to the watch over Bluetooth through Garmin's Connect IQ framework; pairing goes through the Garmin Connect app, which is governed by Garmin's privacy policy. In both cases the data on the watch is the current reading, the trend, and a short recent history.

Notifications

Alerts and coach messages are local notifications created on your phone. They are not sent through a push service and do not involve any server.

The beta

During the beta the app is distributed through Apple's TestFlight. Under TestFlight's terms, Apple may share crash reports and any feedback you choose to send with the developer. Crash reports do not contain your glucose readings or logs. If you email us, we keep the email to reply to you and for nothing else.

This website

afterspike.com is a static site. It sets no cookies and runs no analytics. Fonts are loaded from Google Fonts, which may see your IP address as part of serving them; you can read Google's policy for that service. The site is hosted by a standard web host that keeps ordinary server logs (IP address, time, page requested) for operating the service.

Deleting your data

Deleting the app removes everything it stored on the phone: sensor pairing details, typed readings, the coach's log and its statistics. Readings written to Apple Health stay in Health until you delete them there, because they are your health record and not ours. Logged events in your private iCloud database are removed by deleting the app's data in iCloud settings, or by asking us how.

Children

AfterSpike is not directed at children under 13, and we do not knowingly collect anything from anyone; the app collects nothing about you at all.

Changes

If this policy changes, the date at the top changes and the new version appears here. If a change ever meant data would leave your phone, the app would ask you first.

Contact

Questions about privacy: privacy@afterspike.com Copy