A period tracker that keeps your data on your phone.
Cycle data says more about you than almost anything else on your phone. Here's what to look for in a tracker, and how RhythmHer is built.
Why where the data lives matters
Most cycle apps ask you to create an account before you can log anything. From that moment, your periods, symptoms and moods live on someone else's server, governed by a policy you probably didn't read and can't enforce. The data is valuable: it reveals health conditions, sex life and, in some cases, pregnancy.
"Local-first" means the opposite default. Entries are written to your device, and nothing is uploaded unless you deliberately switch on a feature that needs it.
How to check any period app before you trust it
- Can you use it without an account? If sign-up is mandatory, your data is on a server from day one.
- Does the privacy policy name the data it collects? Vague language usually means broad collection.
- Are there advertising or analytics SDKs? The App Store privacy label shows "Data Used to Track You" if so.
- Can you export and delete everything? Deletion should remove server records too, not just hide them.
- If it syncs, is it encrypted on your device or just in transit? They're very different promises.
How RhythmHer handles it
- No account needed. Install it and start logging; entries are stored on your device.
- Sync is optional and end-to-end encrypted. Entries are encrypted on your phone before upload, so the server holds only ciphertext it can't read. Your password never leaves the device.
- Partner sharing is opt-in and limited. A partner sees only the summary you approve, never raw entries, and you can disconnect at any time.
- Voice notes are transcribed on the device by the phone's own speech recognition; no audio file is recorded, stored or uploaded.
- Face ID lock keeps the app closed on a shared phone.
- Export or delete everything from Profile, including your account and synced records.
The full detail is in our privacy policy, written in plain language.
Questions
Does RhythmHer require an account?
No. Core tracking works with no account and stores entries on your device. An account is only needed if you turn on encrypted sync or partner sharing.
Can RhythmHer read my entries?
No. If you enable sync, entries are encrypted on your phone before they are uploaded, and the encryption key is derived from a password that never leaves your device.
What happens to my data if I delete the app?
Anything stored only on the device goes with it, so export first if you want a copy. If you had an account, you can delete it and its synced records from inside the app.
It isn't on the App Store yet. If you'd like to hear when it launches, email [email protected] and we'll let you know. No list, no marketing — just one message.
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RhythmHer provides general educational information and is not a medical device. It does not diagnose or treat any condition and is not a form of contraception. In an emergency, call your local emergency number.