Your data, plainly

tu-ciclo is a small period tracker I made for myself and a few friends. No company behind it, no ads, no analytics, nothing sold. This page says what happens to what you log, because you should know before you type a single day in.

What gets stored

Exactly what you enter: the days you log (flow, symptoms, mood, energy, libido, sex, pill, context flags, notes, your own tags), your email address so you can sign in, and short-lived sign-in codes (stored hashed, gone after 15 minutes). From your days the app works out your cycles and predictions — those are derived from your entries, never guessed from anywhere else.

Why

Only to show you your calendar, trends and predictions. There is no other use. I don't read your entries, and nothing about them is shared with anyone.

Where it lives

On a server in Falkenstein, Germany (Hetzner), with backups in Hetzner's storage, also in Germany. Sign-in code emails go out through Brevo, a French provider. That is the whole list: nothing leaves the EU, and no third party ever sees your entries.

For how long

As long as you keep your account. Delete it in Settings and everything is wiped immediately; backups expire within 30 days. You can also delete any single day, any time.

What you can do

• Take it with you — Settings → Your data gives you every entry as CSV or JSON.
• Fix anything — every day is editable, and edits save as you go.
• Leave — Settings → Delete account. No questions, no waiting.
• Ask — write to me at hello@tu-ciclo.app about anything here. You also have the right to complain to a data protection authority. I'm based in Berlin, so the one responsible for me is the Berliner Beauftragte für Datenschutz und Informationsfreiheit; the authority where you live works just as well.

The legal bit, in one breath

Cycle data counts as health data under the GDPR, so it is processed only with your explicit consent — creating your account is that consent, and deleting it withdraws it. The person responsible (the "controller") is me, Luz, reachable at the address above.

Honest about the edges

Everything travels encrypted (HTTPS) and the server is locked down, but on your own phone the app opens for whoever is holding it — an app lock is on the list. If that matters for your situation, keep the phone locked and the app off your home screen until then.

Last updated 25 August 2026.