Private Peptide Tracking on iPhone

“Local-first” means the sensitive details that make up your routine remain on your device instead of being stored in PepTrack’s cloud database.

What stays on the device

The current PepTrack privacy policy identifies routine details as local data. That includes logs, user-created schedules, reminders, personal notes, settings, and custom entries.

Deleting the app removes its local data from the device. Before deleting any local-first app, consider whether you need to retain a record through any export options the app provides.

What limited data may leave the device

PepTrack’s published policy describes an optional username and onboarding-completion status stored through Supabase. It also describes anonymous product analytics through PostHog and advertising attribution through Meta.

Those services should not receive routine logs, custom names, notes, or Apple Health values. The privacy policy provides the current details and contact process for data questions.

Apple Health is optional

If you enable Apple Health access, PepTrack can read and write weight data with your permission. The published policy states that this data remains on your device and in your own Apple Health store and is excluded from advertising and analytics.

Questions to ask any routine tracker

• Does the app require an account?
• Are routine logs stored locally or on a server?
• Which analytics and attribution services are used?
• Can permissions be revoked?
• How can server-stored account data be deleted?

Why this matters more here than elsewhere

A routine log is unusually revealing. It records what you take, when, how consistently, and often how you felt — and unlike most health data it is frequently something people prefer not to discuss with an employer, an insurer, or a family member with access to a shared account.

Depending on where you live, this may also fall under consumer health data rules that are stricter than general privacy law. PepTrack publishes a separate Consumer Health Data Privacy Policy covering categories collected, recipients, and how to exercise rights.

What local-first actually means

"Local-first" means the record is written to your device and stays there by default, rather than being sent to a server and mirrored back. The practical difference is what happens when the company disappears, gets breached, or changes its terms: data that never left your phone is not in the blast radius.

The tradeoff is real and worth stating. Local-first data does not sync between devices on its own, and if you lose the phone without a backup, the history goes with it. That is the cost of the guarantee, not an oversight.

Questions worth asking any tracker

• Is an account required? If yes, your data is on a server by definition. If no, ask what is stored anyway.
• What leaves the device, and when? "We don't sell your data" and "your data never leaves your phone" are very different claims.
• What do the analytics capture? Product analytics that record which screens you visited can imply content even without storing it — worth checking whether autocapture is on.
• What happens on delete? Does removing the app remove the record, and does anything persist server-side afterwards?
• Is health-platform access optional? Apple Health integration should be something you switch on, not a precondition.

PepTrack's answers are in its Privacy Policy. The point of the list is that they are the right questions for any tracker, not only this one.