How do I start tracking my cycle?
When you first open Crimson, you'll go through a brief onboarding to set your average cycle length and last period start date. After that, simply tap the "+" button to log your period days, symptoms, and moods. Crimson learns from your data and improves predictions over time.
Is my data stored securely?
Yes. By default, all your data is stored locally on your device and never leaves it. If you choose to enable cloud sync, your data is encrypted end-to-end using Supabase. We never sell or share your personal health data.
Do I need to create an account?
No. Crimson works fully offline without an account. You only need to sign up if you want cloud backup and sync across devices. All core features — tracking, predictions, AI insights — work without an account.
How does the AI assistant work?
The AI chat feature uses your cycle data (current phase, recent symptoms, tracking history) to provide personalized responses. It can answer questions about your cycle, explain symptoms, and offer wellness suggestions. An API key for the AI service is required — you can get a free one from OpenRouter.
How accurate are the predictions?
Crimson uses weighted moving averages that factor in your recent cycles more heavily than older ones. The more cycles you track, the more accurate predictions become. For most users, predictions stabilize after 3–4 tracked cycles.
Can I export my data?
Your data is stored in standard formats and accessible through the app. We're working on a full data export feature for an upcoming release.
The app isn't working correctly. What should I do?
Try closing and reopening the app. If the issue persists, ensure you're running the latest version from the App Store or Google Play. For persistent problems, contact us using the button below with a description of the issue.