Comparison
Flo vs Stardust 2026: Privacy, Funzionalità e Prezzo a Confronto
Our verdict
Flo was caught sharing data with Google and Meta. Stardust marketed privacy after Roe v. Wade but was found by Privacy International to send data to servers and use third-party de-identification. Neither delivers the privacy it promises. PinkyBloom needs no account, has no ads, and never sells your data.
Flo vs Stardust vs PinkyBloom
| Feature | Flo | Stardust | PinkyBloom |
|---|---|---|---|
| Price | ~$49.99/yr premium | Free | Free |
| Users | 440M+ | Millions (post-Dobbs surge) | Growing |
| Data storage | Cloud (Flo servers) | Cloud (de-identified via Rownd) | Stored on your phone |
| Privacy track record | Class action settled 2025; Flo paid $8M | Voluntary law enforcement cooperation | Never sold, no ads; partner sharing end-to-end encrypted |
| AI assistant | Cloud-based chatbot | Built-in AI assistant (Pinky) | |
| Voice logging | |||
| Mood forecasts | |||
| Astrology features | Astrology-themed insights | ||
| Account required | Email required | Google account required | No account needed |
| Safety Mode | Anonymous Mode (still cloud) | ||
| Doctor visit reports | |||
| Ads | Ads in free tier | No ads | No ads ever |
Overview
Flo e Stardust occupano estremi opposti dello spettro dei tracker mestruali in termini di posizionamento del marchio. Flo è il leader di mercato consolidato — 440 milioni di utenti, funzionalità complete e un approccio alla salute aziendale. Stardust è il challenger della privacy post-Dobbs — un'app più piccola che ha visto un aumento dei download dopo la decisione della Corte Suprema, pubblicizzandosi come un tracker mestruale incentrato sulla privacy con approfondimenti a tema astrologico.
Flo offre profondità: chatbot AI, oltre 70 sintomi, forum comunitari, modalità gravidanza e contenuti di oltre 120 esperti medici. Stardust offre differenziazione: approfondimenti sul ciclo mestruale mescolati all'astrologia e messaggi sulla privacy che hanno risuonato con gli utenti improvvisamente preoccupati per i loro dati mestruali.
L'ironia è che nessuna delle due app offre privacy. Le affermazioni di privacy di Stardust non hanno superato l'indagine indipendente. Per gli utenti che si preoccupano della privacy dei dati riproduttivi — specialmente in un contesto post-Dobbs — nessuna delle due app fornisce protezione architettonica.
Privacy comparison
The privacy comparison between Flo and Stardust is a case study in two different kinds of failure.
Flo's data sharing is documented in an FTC complaint and a federal class action. Menstrual data went to Google, Meta, and analytics firms. Flo paid $8M to settle in 2025, admitting nothing. A California jury found Meta liable for eavesdropping. Flo did the thing everyone fears a period tracker will do.
Stardust positioned itself as the antidote to Flo's failures. After the Dobbs decision, it marketed privacy and surged in downloads. But in June 2022, Vice/Motherboard discovered Stardust's privacy policy stated it would cooperate with law enforcement "whether or not legally required" — meaning voluntary handover of menstrual data to police. Stardust changed the wording only after press inquiry.
Then in May 2025, Privacy International revealed deeper issues: Stardust sends data to servers and relies on Rownd, a third-party de-identification service. A Google account is required, linking your menstrual data to Google's identity ecosystem. De-identification is a process, not a guarantee — academic research shows menstrual data can be re-identified with few data points.
PinkyBloom needs no account and never sells your data. Your cycle log is stored on your phone, with no third-party de-identification services. Safety Mode swaps neutral data into what she shares with a partner.
Features and intelligence
Flo's feature set dwarfs Stardust's. AI chatbot, 70+ symptoms, community forums, pregnancy mode, and thousands of articles. Flo is a comprehensive health platform.
Stardust's main differentiator is astrology-themed cycle insights — connecting your cycle to astrological concepts. The tracking itself is basic: cycle predictions and symptom logging. For users who enjoy the astrology angle, it's engaging. For users who want health intelligence, it's limited.
PinkyBloom provides genuine AI intelligence. Pinky, the built-in AI assistant, handles health conversations, voice logging captures symptoms naturally, mood forecasts predict emotional patterns, and doctor visit reports create professional summaries. It's the substance that both Flo's chatbot and Stardust's astrology insights point toward.
Pricing comparison
Flo charges ~$49.99/year for premium; its free tier has ads. Stardust is free with no ads.
Both apps store data in the cloud. Flo monetizes through subscriptions and (historically) advertising partnerships. Stardust's monetization model is less clear, but the Google account requirement and server-side data processing suggest data plays a role.
PinkyBloom is free. No ads, no Google account linkage. The total cost is $0.
There's a better option
Flo betrayed user trust with documented data sharing. Stardust promised privacy but relies on servers and third-party de-identification. PinkyBloom has no accounts to identify you, no ads, and never sells your data. Safety Mode replaces her shared status with neutral data, which neither app offers.
