Luna is the full-featured cycle app for people who need more than local-only apps like drip and Euki can offer — EU-hosted, encrypted on the device (AES-256), with no ad tracking. This comparison is honest about where Luna fits — and where another app is the better choice. About other providers we only state what is uncontroversial.
✓ = yes · ✗ = no · “not assessed” = we deliberately make no claim here — please check directly with the provider.
| Luna | Flo | Clue | drip | Euki | |
|---|---|---|---|---|---|
| Open source | ✗¹ | partly (Anonymous Mode libraries) | not assessed | ✓ | ✓ |
| Local-only (no server) | ✗ | ✗ | ✗ | ✓ | ✓ |
| Sync across devices | ✓ | ✓ | ✓ | ✗ | ✗ |
| Account required | ✓ | usable without an account in Anonymous Mode⁴ | not assessed | ✗ | ✗ |
| Server location | EU (Hetzner, self-hosted) | USA (per own policy)⁴ | EU (per provider)⁴ | n/a (no server) | n/a (no server) |
| Encrypted on device before sync | ✓ (AES-256) | not assessed | not assessed | n/a² | n/a² |
| Zero-knowledge option | ✓ (Maximum Privacy mode) | not assessed | not assessed | ✓ (local by design) | ✓ (local by design) |
| Ad SDKs (Exodus report) | none — 1 tracker: Sentry, crash reporting (report) | check yourself | check yourself | check yourself | check yourself |
| Life phases covered | cycle, pregnancy, breastfeeding, perimenopause & menopause + fertility-treatment documentation | cycle, pregnancy, perimenopause (per provider)⁴ | cycle, pregnancy, perimenopause — modes, partly Clue Plus (per provider)⁴ | focus on cycle | focus on cycle |
| Price model | free basics + subscription/pass | free basics + subscription | free basics + subscription | free | free |
¹ Publishing the encryption layer is planned (after the US launch), no date promised.
² drip and Euki do not sync — data never leaves the device, so pre-upload encryption does not apply.
³ Source: Exodus Privacy, as of July 2026.
⁴ Flo/Clue details as published by the providers themselves (privacy policy, support and product pages), as of August 2026 — no guarantee, please verify there.
Every claim about the Luna cycle app with its source
Want an app whose source code anyone can read, with data that never leaves your phone — no account, no server? Then pick drip or Euki. Both are open source, deliberately minimal, and genuinely good at exactly that. The trade-off is part of the design: having no server also means nothing moves to a new phone by itself and nothing is backed up across devices.
Luna is built for people who want a full companion across all four life phases — cycle, pregnancy, breastfeeding, menopause — with the comfort of a modern app:
Many of these features exist in other apps too. Luna pairs this feature set with EU hosting and on-device encryption — no ad tracking, funded by subscriptions rather than data. That combination is the yardstick you can hold any app to.
Whatever provider you choose — including Luna — check the server location, an independent tracker report and the privacy policy.
→ Every claim about the Luna cycle app with its source
Four things, whichever provider you choose: where the servers are, whether an independent tracker report exists (Exodus Privacy), whether the app is funded by subscriptions or by data, and whether you can export and delete your data. This applies to Luna too.
Because we only state what is either about Luna itself, uncontroversial, or published by the providers themselves — with source and date. Where none of that applies, we deliberately make no claim instead of guessing.
Yes — for anyone who wants a full-featured tracker with EU hosting, on-device encryption and no ad tracking. The table above shows the differences in detail, including where other apps are the better fit.