How it works
Your data and privacy
PepCycle stores your log on your device. If iCloud is enabled it syncs through your Apple account's private database — not ours. There is no PepCycle account, no PepCycle server holding health entries, and therefore nothing for us to lose, sell or hand over.
Last updated
The model in one diagram
Your iPhone
The local database. Compounds, vials, entries, sites, observations. Works with no network at all.
Your iCloud
A private-database copy under your Apple ID, used to restore onto a new device. Apple's infrastructure, your account.
PepCycle servers
Not in the path. No account, no log storage, no analytics on your health entries.
Why we built it this way
A peptide and GLP-1 log is unusually sensitive. It records what someone takes, how often, and what it does to them — information that is nobody else's business and that has real consequences if it leaks. The safest way to protect data is not to hold it.
That choice has a cost, and we would rather be straight about it than pretend otherwise: no web log-in, no Android app, and no way for us to recover your data if you lose both your device and your iCloud. Those are consequences of the architecture, not oversights. See the trade-off explained in full.
What we do collect
One thing: subscription status, handled through our payments provider so the app knows whether Pro is active. That is a purchase record, not a health record, and it contains nothing about what you log.
- Collected: purchase and subscription status.
- Not collected: compounds, vials, doses, injection sites, side effects, weight, notes, contacts, or any other health data.
- No advertising SDKs, no data brokers, and no sale of anything to anyone.
The formal version, including our processors, is in the Privacy Policy.
Preventing the failure everyone actually reports
The complaint that recurs across every long-lived tracking app is not a hack. It is “an update lost my history.” Three things guard against it:
- Versioned schema migrations. Each app update migrates your database forward rather than recreating it. A migration that cannot run safely does not run at all.
- iCloud sync, so a lost device is not a lost log. Sign in on a new phone and the history restores.
- Complete export. Sync is not backup — it propagates deletions faithfully. A file you hold is the only real backup, which is why export includes vials, concentrations and blend components rather than a flattened summary. How and when to export.
This website
- The calculators run entirely in your browser. Nothing you type into them is transmitted, logged or stored — the arithmetic happens on your device.
- No advertising trackers and no cross-site profiling.
- Fonts are loaded from Google Fonts; everything else is served from this domain.
- Aggregate analytics tell us which pages are read. They are not linked to any health information, because this site never receives any.
Frequently asked questions
Where is my PepCycle data stored?
In a database on your iPhone. If you have iCloud enabled, a copy syncs to your personal iCloud private database, which is your Apple account rather than ours. There is no PepCycle server holding health entries.
Do I need an account to use PepCycle?
No. There is no sign-up, no email address and no password. The app works fully offline from first launch.
Can PepCycle staff see my log?
No. Health entries never reach our infrastructure, so there is nothing for us to look at. That is an architectural fact rather than a policy promise.
What data does PepCycle collect at all?
Purchase and subscription status, processed through our payments provider so the app knows whether Pro is active. Health entries — compounds, vials, doses, sites, side effects — are not collected.
What happens to my data if PepCycle shuts down?
It stays where it already is: on your device and in your own iCloud. You can export a complete CSV or JSON copy at any time, including vial concentrations and blend components.
A log that outlives the app
On-device storage, your own iCloud, versioned migrations and a complete export. Four separate defences against the failure that ends most tracking habits.
Free to download · No account required · Price shown before you enter anything personal