Coming soon to iOS · Join the waitlist

Know your cycle.
Own your rhythm.

Privacy-first period tracking with AI predictions that learn your unique rhythm. All on your device — never in the cloud.

On-device AI · End-to-end encrypted sync Built by CrownLabs
14
Day · cycle
Ovulation
Menstrual Follicular Ovulation Luteal
Built around the things that matter
Features

Every feature for cycle confidence.

Designed with the realities of menstrual health: accurate, private, and quiet enough to disappear into your day.

AI predictions

On-device Core ML targets high prediction accuracy and adapts to your unique cycle. No cloud calls, no leaks.

90%+
Target accuracy
Statistical + ML hybrid
that learns your rhythm

Smart calendar

Visual cycle calendar showing phases, fertile windows, and predictions at a glance.

Privacy first

On-device only. Optional E2E-encrypted iCloud sync.

Symptom tracking

Log cramps, mood, energy, flow intensity, sleep — all in seconds. Build a portrait of your body across cycles.

Cramps Mood Energy Flow Sleep Headache

HealthKit sync

Talks to Apple Health for a complete view alongside sleep, activity, and heart data.

Insights & analytics

Trend charts, cycle averages, and anomaly detection so you can spot irregularities early.

How it works

Three steps. Real rhythm.

Getting started takes less than a minute. The longer you use it, the smarter it gets.

1

Log

Track your period, symptoms, and mood with a few taps. Skip the questionnaire onboarding.

2

Learn

On-device AI analyzes your data to find patterns and predict your next cycle.

3

Thrive

Personalized insights, anomaly alerts, and a visual portrait of your cycle over time.

Pricing

Planned pricing.

Free forever for the basics. Premium unlocks AI predictions, unlimited history, and analytics — when launched.

Pre-launch · Waitlist members lock in launch pricing
Free
$0
forever
  • Basic period tracking
  • Visual cycle calendar
  • 3-month history
Join free waitlist
Lifetime
$79.99 once
all future updates included
  • Everything in Premium
  • Lifetime access
  • All future updates
Notify me
FAQ

Questions, answered.

What is Shark?
Shark is a privacy-first menstrual cycle and period tracking app for iOS. It uses on-device Core ML to predict cycles accurately while keeping all your data local.
When does it launch?
Shark is currently in active development. Join the waitlist and you'll be the first to know — and you'll lock in launch pricing.
Is my period data private?
Yes. Shark is built with privacy at its core. All data stays on your device. Predictions run entirely on-device using Core ML. Optional iCloud sync is end-to-end encrypted and controlled entirely by you.
How accurate are predictions?
Shark uses a hybrid of statistical models and Core ML. Target accuracy is 90%+ once trained on your data — accuracy improves as more cycles are logged.
What platforms are supported?
iOS first. Android is on the roadmap but not committed yet.

Ready to understand your cycle?

Join the waitlist. Get early access, launch pricing, and the occasional honest update — no spam.

Join the waitlist