PinkyBloom vs Stardust: Provably Private After Roe v. Wade

Stardust gained millions of downloads in the wake of the Dobbs decision by marketing itself as a privacy-first period tracker. The messaging resonated with users who were suddenly concerned about their menstrual data being used against them. But Privacy International's May 2025 investigation revealed a gap between Stardust's marketing and its actual data practices.

The core issue is architectural. Stardust doesn't keep data on your device — it sends data to its servers and relies on Rownd, a third-party de-identification service, to strip identifying information. De-identification is a process, not a guarantee. Academic research has demonstrated that menstrual cycle data can be re-identified with relatively few data points, especially when combined with other information.

Perhaps most concerning: Stardust requires a Google account to sign up. This immediately links your menstrual tracking to Google's identity ecosystem. PinkyBloom requires no account of any kind. Your data never leaves your iPhone, and there's no third-party de-identification service because there's nothing to de-identify. The privacy isn't promised — it's architecturally enforced.

Stardust differentiates itself with astrology-themed cycle insights, blending period tracking with horoscope-style content. While this creates an engaging user experience, the actual health intelligence is relatively basic — standard cycle predictions and symptom tracking without advanced AI capabilities.

PinkyBloom offers a fundamentally different level of intelligence. The on-device AI assistant processes your health data using Apple's Core ML to generate personalized insights, cycle predictions, and mood forecasts. Voice logging lets you describe symptoms naturally and the AI extracts structured health data. The doctor visit report generator creates professional summaries for healthcare appointments.

The difference is substance vs. style. Stardust wraps basic tracking in astrology aesthetics. PinkyBloom delivers genuine AI-powered health intelligence — mood forecasting, multi-symptom analysis, and natural language understanding — all running locally on your iPhone's Neural Engine.

Switching from Stardust to PinkyBloom is quick and easy. Open Stardust's calendar view, take a screenshot, and use PinkyBloom's Screenshot Import feature. The OCR engine extracts your cycle history automatically.

For users who downloaded Stardust specifically for post-Roe privacy, switching to PinkyBloom is especially important. While Stardust markets privacy, its architecture still relies on cloud storage and third-party de-identification. PinkyBloom's on-device architecture provides the privacy guarantee that Stardust promises but doesn't fully deliver.

After importing your data, consider deleting your Stardust account and revoking its access to your Google account. Given that Stardust requires Google sign-in, removing that connection ensures your menstrual data is no longer linked to your Google identity.

Both Stardust and PinkyBloom are free, so the comparison isn't about price — it's about what you get for free. Stardust offers basic period tracking with astrology-themed content. PinkyBloom offers on-device AI, voice logging, mood forecasts, doctor visit reports, encrypted partner sharing, home screen widgets, and a health vault with Face ID.

The feature gap is enormous. PinkyBloom includes capabilities that most paid period trackers don't offer, let alone free ones. And every feature runs on-device, meaning you get more functionality with stronger privacy.

For users who chose Stardust because of its privacy messaging, PinkyBloom delivers what Stardust promised. Real privacy through on-device architecture, not marketing claims backed by third-party de-identification. And you get significantly more features in the process.