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Bluemoon vs Clue: catalog facts
Bluemoon	Clue
Best for: People who want a private, simple period tracker on Android	Best for: People who want to track their menstrual cycle on their phone
Free Free and open source.	Free + paid options Free app with a paid subscription for additional features.
Android	Android, iOS
Data stays on the device Simple interface All 3 strengths for Bluemoon Data stays on the device Simple interface Available on F-Droid and Google Play	Cycle predictions and personalised insights Available on both iOS and Android All 3 strengths for Clue Cycle predictions and personalised insights Available on both iOS and Android Science-based approach to content
Android only Focused on basic tracking rather than detailed health insights	Some features require a subscription Sensitive health data is handled by a commercial service
Downloadable app	Downloadable app
Open source	Not open source
License: GPL-3.0-or-later	License not stated
No account needed	Not stated if an account is needed
Offline features available	Not stated if it works offline
Official website Full listing and sources Sources for Bluemoon nilsgrob.ch/work/bluemoon Catalog checked October 2, 2026	Official website Full listing and sources Sources for Clue helloclue.com play.google.com/store/apps/details apps.apple.com/us/app/clue-period-cycle-tracker/id657189652 Catalog checked September 23, 2026

“Not stated” means we have not confirmed it. Features can vary by device and plan.