Period tracking that protects your privacy.
Your cycle data is yours. We mean that literally.
Most period tracking apps are free because they make money from your data. That data gets sold to advertisers, shared with data brokers, and in some US states has been requested by law enforcement. We found this unacceptable. So we built Clio Daye.
Everything you track in Clio Daye lives only on your device. There is no account to create, no server receiving your data, no cloud backup, no subscription, no ads. We have no access to your data. Nobody does except you.
That was the whole reason we built this.
How it works
Clio Daye covers the things that matter in day-to-day cycle tracking. You can log flow intensity, 15 different symptoms, mood, and notes. It shows your current cycle phase and predicts when your next period is likely to start, with an honest uncertainty range rather than a false-precision date. Over time, it surfaces patterns in your flow, symptoms, and mood so you can see what your own cycle actually looks like.
Most apps tell you when your next period is due. Clio Daye shows you a rolling six-month picture of your cycle so you can plan ahead, not just react. Useful for travel, events, or simply knowing what kind of week you're heading into.
Everything is protected by Face ID, Touch ID, or a PIN. If someone else picks up your phone, they cannot open the app without your permission.
Who it's for
Anyone who has a menstrual cycle. Clio Daye uses body-neutral language and doesn't assume gender. It's designed for people across all life stages, from first cycles through perimenopause.
A lot of people who try Clio Daye have already had a bad experience with another app. Maybe you found out your previous app shared your data in ways you never agreed to. We built this for exactly that reason.
Open source and free, forever
Clio Daye is free with no subscription, no premium tier, and no advertising. The source code is public at github.com/pjaol/safeflow so anyone can read it and verify the privacy claims for themselves. We're not a venture-backed startup optimizing for growth. We're a small team who thought this tool should exist and built it.
A note on what this isn't
Clio Daye is not a contraceptive tool and should not be used as one. Predictions are estimates based on your logged history and become more accurate as you log more cycles. If you need contraception or have medical concerns about your cycle, please talk to a healthcare provider.
Requires iOS 17.5 or later.
Ratings & Reviews
This app hasn’t received enough ratings or reviews to display an overview.
This update brings full accessibility support and multiple language improvements.
— VoiceOver support throughout the app — every screen is fully navigable with assistive technologies
— Screen labels, cycle phase descriptions, and data summaries are all readable by VoiceOver
— Improved contrast and dynamic type support across all views
— The app now fully supports German, French, and Spanish
Your data remains on your device. Nothing has changed there.
Version 1.1.1
The developer, patrick o'leary, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Privacy practices may vary, for example, based on the features you use or your age. Learn More
The developer indicated that this app supports the following accessibility features. Learn More
Supported Features
VoiceOver
Voice Control
Larger Text
Dark Interface
Differentiate Without Color Alone
Sufficient Contrast
Reduced Motion
Information
Seller
patrick o'leary
Size
4 MB
Category
Health & Fitness
Compatibility
Requires iOS 26.0 or later.
iPhone Requires iOS 26.0 or later.
Mac Requires macOS 26.0 or later and a Mac with Apple M1 chip or later.