Privacy Policy
Last Updated: April 3, 2026
Welcome to Kramster. This Privacy Policy explains how we collect, use, and protect your information when you use our flashcard learning application. We are committed to protecting your privacy and ensuring transparency about our data practices.
1. Information We Collect
1.1 Information You Provide
- Flashcard Content: All flashcard decks, notes, and study materials you create or import are stored locally on your device. We do not have access to this content.
- Imported Decks: When you import .apkg files from Anki or other sources, the content remains on your device only.
- App Settings: Your preferences such as language (English/Russian), theme, and learning parameters are stored locally.
- AI Deck Crafting (Premium Feature): If you use the AI-powered deck crafting feature, the text prompts you provide are sent to our backend servers for processing and deck generation. Generated decks are stored temporarily on our servers until you download them, after which they are deleted within 30 days.
1.2 Automatically Collected Information
We use analytics services to understand how our app is used and to improve user experience. The following data is collected automatically:
- Usage Analytics: App launch events, session duration, screen views, and feature usage
- Device Information: Device type, operating system version, app version
- App Performance: Crash reports and error logs to help us identify and fix bugs
- User Engagement: Interaction patterns within the app (e.g., when cards are studied, flipped, or answered)
Important: We do NOT collect the content of your flashcards, personal identifying information (name, email, phone number), or location data.
2. How We Use Your Information
The information we collect is used exclusively for the following purposes:
- App Functionality: To provide core features like spaced repetition scheduling, card reviews, and deck management
- Performance Improvement: To identify and fix bugs, crashes, and performance issues
- User Experience: To understand which features are most used and improve the app accordingly
- Analytics: To track general usage patterns and trends (aggregated, non-personal data)
3. Data Storage and Security
3.1 Local Storage
All your study content, including flashcards, decks, notes, and media files (images, audio, video), is stored locally on your device using SQLite database. This data never leaves your device unless you explicitly export or share it.
3.2 Cloud Analytics
Anonymous usage data and crash reports are sent to our analytics providers (Firebase Analytics and Amplitude) over secure, encrypted connections. This data does not include your personal information or flashcard content.
3.3 Security Measures
We implement industry-standard security measures to protect your data:
- Encrypted data transmission (HTTPS/TLS)
- Secure local database storage
- Regular security updates and patches
- Your flashcard content remains on your device; only AI craft prompts and metadata are transmitted to our servers when using premium features
4. Third-Party Services
Kramster uses the following third-party services that may collect information:
4.1 Firebase (Google)
4.2 Amplitude
- Purpose: Product analytics and user behavior insights
- Data Collected: App usage events, session data, device information
- Privacy Policy: https://amplitude.com/privacy
4.3 RevenueCat
- Purpose: In-app subscription and payment processing
- Data Collected: Purchase receipts, subscription status, product identifiers, transaction tokens (processed through Apple App Store and Google Play Store)
- Privacy Policy: https://www.revenuecat.com/privacy
4.4 Kramster Backend Services
- Purpose: Premium features (AI deck crafting), subscription validation, push notifications
- Data Collected: Anonymous device identifiers, subscription status, AI deck crafting prompts, push notification tokens
- Data Storage: Hosted on secure servers; AI prompts and generated decks are retained for up to 30 days after creation
- Security: All communications use HTTPS/TLS encryption; no personal identifying information is collected
All services are configured to respect user privacy and comply with data protection regulations including GDPR and CCPA.
5. Your Rights and Choices
You have the following rights regarding your data:
5.1 Data Access and Deletion
- Local Data: You can view, export, or delete all your flashcard data directly from the app settings
- Analytics Data: You can request deletion of analytics data by contacting us at the email below
- Complete Removal: Uninstalling the app removes all local data from your device
5.2 Opt-Out Options
While we do not currently offer in-app analytics opt-out, you can:
- Use device-level privacy settings to limit app tracking (iOS: Settings → Privacy → Tracking; Android: Settings → Privacy → Ads)
- Contact us to request analytics opt-out for your device ID
6. Children's Privacy
Kramster is suitable for users of all ages. We do not knowingly collect personal information from children under 13 years of age. If you are a parent or guardian and believe your child has provided personal information to us, please contact us immediately.
7. International Data Transfers
Your analytics data may be processed and stored on servers located outside your country of residence. Our third-party service providers (Firebase, Amplitude) comply with international data protection standards and regulations.
8. Changes to This Privacy Policy
We may update this Privacy Policy from time to time to reflect changes in our practices or legal requirements. When we make significant changes, we will:
- Update the "Last Updated" date at the top of this policy
- Notify users through the app (if applicable)
- Post the updated policy on our website
We encourage you to review this Privacy Policy periodically to stay informed about how we protect your data.
9. Contact Us
10. Legal Compliance
This Privacy Policy complies with applicable data protection laws and regulations, including:
- GDPR (General Data Protection Regulation) for users in the European Union
- CCPA (California Consumer Privacy Act) for users in California
- COPPA (Children's Online Privacy Protection Act) for users under 13
If you are located in the European Union, you have additional rights under GDPR, including the right to data portability, the right to rectification, and the right to lodge a complaint with a supervisory authority.
11. Data Retention
We retain different types of data for different periods:
- Local Study Data: Retained on your device until you delete it or uninstall the app
- Analytics Data: Retained by our service providers for up to 14 months for Firebase and 12 months for Amplitude
- Crash Reports: Retained for 90 days to allow for debugging and fixing issues
- AI Craft Prompts and Generated Decks: Retained on our servers for up to 30 days after creation, then automatically deleted
12. Your Consent
By using Kramster, you consent to this Privacy Policy and agree to its terms. If you do not agree with this policy, please do not use the app.
Thank you for using Kramster. We are committed to protecting your privacy and providing you with the best learning experience.