Privacy Policy

Last Updated: 17.08.2025

1. Data Controller

Name: Felix Krüger
Address:
Offenbacher Landstraße 522
60599 Frankfurt am Main
Country: Germany

2. Collection and Processing of Personal Data

2.1 Legal Basis

We process personal data only where legally permitted or with your consent, based on the EU General Data Protection Regulation (GDPR).

2.2 Automatically Collected Data

Device Information: Operating system, app version, device ID
Usage Data: App areas visited, session duration, feature usage
Technical Data: IP address, timestamps, error messages

Legal Basis: Art. 6 para. 1 lit. f GDPR (legitimate interest in proper app functionality)

2.3 Firebase Services (Google)

Our app uses Google Firebase services:

Firebase Authentication:

Data: User ID, email address (for Google sign-in), anonymous IDs
Purpose: User identification, access management
Legal Basis: Art. 6 para. 1 lit. b GDPR (contract performance)

Cloud Firestore:

Data: Stored wiki articles, bookmarks, ratings
Purpose: Data storage and synchronization
Legal Basis: Art. 6 para. 1 lit. b GDPR (contract performance)

Firebase Analytics:

Data: Anonymized usage statistics, device information
Purpose: App improvement, error analysis
Legal Basis: Art. 6 para. 1 lit. f GDPR (legitimate interest)

2.4 AI-Generated Content

Input Data: Your search queries and topic inputs
Processing: Server-side AI analysis for content creation
Storage: Generated content is stored in the database
Legal Basis: Art. 6 para. 1 lit. b GDPR (contract performance)

2.5 Advertising and Monetization

Google Mobile Ads:

Data: Advertising ID, device information, usage behavior
Purpose: Personalized advertising, revenue generation
Legal Basis: Art. 6 para. 1 lit. a GDPR (consent) or lit. f (legitimate interest)

Affiliate Links:

Data: Product link clicks, purchasing behavior (aggregated)
Purpose: Revenue generation through commissions
Legal Basis: Art. 6 para. 1 lit. f GDPR (legitimate interest)

2.6 Premium Subscriptions

In-App Purchases:

Data: Subscription status, purchase history, payment information (via App Store/Play Store)
Purpose: Service delivery, subscription management
Legal Basis: Art. 6 para. 1 lit. b GDPR (contract performance)

3. Data Transfer to Third Parties

3.1 Google (Firebase/Cloud Services)

Location: EU (Ireland) and USA (with EU Standard Contractual Clauses)
Purpose: Cloud hosting, analytics, authentication
Safeguards: EU Standard Contractual Clauses, adequacy decision

3.2 Affiliate Partners

Amazon: Germany, Europe, international locations
Other Retailers: Depending on chosen affiliate link
Data: Only aggregated, non-personal statistics

4. Retention Periods

Account Data: Until account deletion
Usage Data: 26 months (Google Analytics standard)
AI Content: Indefinitely (to prevent duplicates)
Advertising IDs: 12 months

5. Your Rights (GDPR)

Access (Art. 15 GDPR): Information about processed data
Rectification (Art. 16 GDPR): Correction of incorrect data
Erasure (Art. 17 GDPR): "Right to be forgotten"
Restriction (Art. 18 GDPR): Limitation of processing
Data Portability (Art. 20 GDPR): Export your data
Objection (Art. 21 GDPR): Object to processing
Complaint (Art. 77 GDPR): With supervisory authorities

Contact for Data Rights: support@kruxdev.com

6. Right of Withdrawal

Consent can be withdrawn at any time with effect for the future. Withdrawal does not affect the lawfulness of processing until withdrawal.

7. Data Security

Encryption during data transmission (TLS)
Access restrictions
Regular security updates
Firebase Security Rules

8. Minors

The app is not specifically directed at children under 16. If we become aware of data from minors without consent, it will be deleted.

9. Changes

This privacy policy may be updated due to legal or technical changes. The current version is always available in the app.

Supervisory Authority:
Bundesbeauftragte für den Datenschutz und die Informationsfreiheit
Graurheindorfer Str. 153, 53117 Bonn
poststelle@bfdi.bund.de