Last updated: October 15, 2026
StackLog (“the App”) is a personal, on-device supplement tracking app published by Ryan Fritz.
StackLog does not require an account and does not collect personal data on our servers. There is no developer backend, analytics SDK, advertising network, or crash reporter in the App.
Supplement names, doses, schedules, Taken/Skip logs, supply estimates, settings (including optional body weight, sex and activity level, used only to show a personalized protein reference range), and optional reminders are stored locally on your device. This information stays on your device unless you choose to export or share it.
If you subscribe to StackLog Pro and turn on Sync to Apple Health in Settings, the App asks iOS for permission to write data to Apple Health. When you mark a dose as Taken, the App saves the amount as a nutrition sample (for example 50 mcg of vitamin D or 200 mg of magnesium) together with the supplement name and the time you logged it. If you undo or skip that dose, the App deletes the sample it wrote.
StackLog only writes to Apple Health. It does not read any of your Health data. Data the App writes to Apple Health stays on your device and in Apple Health under Apple’s own privacy protections. It is never sent to us or to any third party, and it is not used for advertising, marketing, or data mining.
You can turn the feature off at any time in the App’s Settings, change which data types StackLog may write in the Health app (profile → Apps → StackLog), and delete samples StackLog wrote from the Health app.
If you use backup or clinician summary features, the App creates a file you can share through the system share sheet. That sharing is initiated by you. We do not receive those files.
Optional local reminders are scheduled on your device only. We do not send push notifications from a server.
The App does not track you across apps or websites and does not use the advertising identifier (IDFA).
The App is not directed at children under 13. It does not knowingly collect personal information from children.
StackLog is a personal tracker, not a medical device. It does not provide medical advice and does not diagnose, treat, cure, or prevent disease.
If the App later adds analytics, accounts, or a server, this policy will be updated before those features ship.
Questions about privacy: rfritz@dc.rr.com