Switch from Stardust
Leaving a period app is usually about one quiet preference: where your cycle, sex, and contraception notes live. Stardust is a cloud period tracker with subscriptions. Lua is a privacy-first iOS alternative built so those logs never leave your phone.
Why switch from Stardust to a private period tracker
Stardust is built around an account and company servers. Contact details typically go through Rownd. Stardust says health data is stored against a random account ID and claims that ID is not linked to your contact information. The company also says it does not sell data.
Independent reporting (including Mozilla, Privacy International, and BBC coverage) has described third-party analytics and attribution pipelines — RudderStack among them — and named marketing partners such as Meta and AppsFlyer in that reporting. Some of that coverage discussed reproductive-health-related data in those pipelines. Stardust has disputed some characterizations, including framing that treated pipeline participation as selling health data. This page does not claim Stardust sells health data. Treat current encryption claims carefully: TechCrunch reported that earlier end-to-end encryption language was scrubbed; what remains is the ordinary SSL-plus-server-side model, not a verified on-device E2E design.
Lua takes a different path. There is no Lua account. There is no Lua server for health logs. Bleeding, sex, symptoms, mood, contraception, and pregnancy entries stay in private storage on your iPhone. No ads, no ad IDs, no crash reporters. The app sends anonymous usage analytics through PostHog; your entries stay on your phone.
If you want the longer evidence table — Lua next to Flo, Clue, Euki, and drip on the three axes that matter — read private period tracker apps.
Stardust vs Lua: what actually differs
This table sticks to structural privacy and the locked Lua free / Lua+ gate. Stardust’s subscription feature set changes over time — check Stardust for what is gated today. Lua’s free and Lua+ columns are exact.
| Feature | Stardust (typical) | Lua free | Lua+ |
|---|---|---|---|
| Account | Yes (typical Apple / Google login) | No | No |
| Health logs on company servers | Yes — cloud storage; Stardust claims health data sits against a random account ID not linked to contact info | No | No |
| Ads / health telemetry | Independent reports of analytics / attribution SDKs (e.g. RudderStack, Meta, AppsFlyer named in reporting); Stardust disputes some characterizations — check Stardust’s current policy | No ads; anonymous usage via PostHog | Same |
| Log bleeding | Yes | Yes | Yes |
| Calendar, period predictions and cycle insights | Yes (typical) | Yes | Yes |
| Log sex / symptoms / mood (daily check-in) | Yes (typical) | Yes | Yes |
| Method screens and reminders (pill, patch, ring, shot, IUD, implant) | Varies, check Stardust | No | Yes |
| Period and check-in reminders | Check Stardust | Yes | Yes |
| Stats cards | Often subscription / paid, confirm in-app | Some | All |
| TTC and pregnancy modes | Check Stardust | No | Yes |
| Next-period confidence detail and PDF export | Check Stardust | No | Yes |
| Cross-device cloud sync | Yes (account / cloud) | No | No |
| Face ID / biometric lock | Check Stardust | Optional | Optional |
| Platform | iOS and Android | iOS only | iOS only |
Lua+ in the US is $6.49 a month or $39.99 a year, billed by Apple. Period, sex and check-in logging stay free either way.
What else Lua does differently
Local reminders. If you use Lua+, method reminders are scheduled on the device. They still fire in airplane mode. There is no push server and no push token for those clocks.
Optional Face ID. A biometric lock can gate the screen. iOS checks the face or fingerprint; Lua never sees it. That lock is not a second encryption layer on the file — your iPhone’s device encryption is what protects on-disk storage when you have a passcode.
Optional Apple Health. Off by default. Lua reads periods, temperature and HRV from Health, and writes back only the periods you log.
iOS only. There is no Android app. If you need Android, local-first peers such as Euki and drip are worth a look on the comparison page.
How to switch from Stardust to Lua
Lua cannot import a Stardust export. Past periods can be entered by hand, or brought in from Apple Health if Health already has them. The move is short.
- Decide to leave Stardust. Export or screenshot anything in Stardust you want as a personal reference. Lua will not pull Stardust’s cloud history.
- Install Lua from the App Store. Open it and start logging. No account, no email.
- Optional: Apple Health. In Lua, turn on Apple Health if you want. The toggle is off by default. Lua can read up to 12 months of past periods, basal body temperature and HRV from Health, and writes back only the periods you log in Lua.
- Re-log what Health does not cover. Symptoms, sex, mood, and contraception details that never lived in Health need to be entered again, or left behind if you prefer a clean start.
- Add Lua+ if you want method reminders. The pill, patch, ring, shot, IUD and implant screens and their reminders are part of Lua+. The calendar, predictions, cycle insights, and logging your period, sex and daily check-in are free.
Soft next step
If the reason you are leaving Stardust is that you want the log on your phone and nowhere else, Lua on the App Store is built for that. For the full privacy comparison with Flo, Clue, Euki, and drip, see private period tracker apps.
Frequently asked questions
The things people ask us most.
Does Stardust require an account?
Typically yes — Stardust is built around an account, often with Apple or Google login. Contact details typically go through Rownd. Lua has no account path at all.
Does Lua store my cycle on its servers?
No. There is no Lua server for health logs. Entries stay on your iPhone.
Will switching delete my old app data?
Installing Lua does not touch your old app. What happens to that account, export, or deletion is their process — follow their settings and support if you want that history removed from their side.
Can I import my history into Lua?
Yes, from Flo or Clue. Save an export from that app, then in Lua open Settings, then Import data, and choose the file. It is read on your phone. Lua cannot import from Stardust or Clover, so past periods from those apps can be entered by hand, or brought in from Apple Health if Health already has them.
Is Lua free?
Lua is free to download, with no ads. The free version covers the calendar, period predictions and cycle insights, logging your period and sex, the daily check-in for symptoms, mood and energy, and reminders for your expected period and the daily check-in. Lua+ adds the pill, patch, ring, shot, IUD and implant screens and their reminders, trying to conceive and pregnancy modes (temperature, mucus and ovulation tests, kicks and contractions), the next-period confidence detail, all Stats cards, and PDF export. Lua+ is a monthly or yearly subscription billed by Apple, and you can cancel any time in your Apple Account subscription settings. Deleting the app does not cancel a subscription. Details are in our terms.
One app for your cycle, contraception, fertility and pregnancy.
Private, flexible and designed to adapt with you.