Android App Privacy Policy
Last updated: October 3, 2026
Quick Summary
What We Collect
- Device ID hash (anonymous)
- AI Scanner images (temporary)
- Usage quotas for limits
What We DON'T Collect
- Personal names or emails
- Location data
- Contacts or phone numbers
- Browsing history
How We Use Data
- Anonymous authentication
- Process AI scan requests
- Enforce usage quotas
- Provide exchange rates
What We Never Do
- Sell your data to third parties
- Show personalized advertising
- Share your personal information
Currency Wiki ("we," "our," or "us") is committed to protecting your privacy. This Privacy Policy explains how we collect, use, and safeguard information when you use our Android application ("App"). We designed this App with privacy in mind - no personal accounts required and minimal data collection. Free users see non-personalized ads, while Pro subscribers enjoy an ad-free experience.
1. Information We Collect
We collect only the minimum information necessary for the App to function:
Device ID Hash
A one-way cryptographic hash (SHA-256) of your Android device ID. This cannot be reversed to identify your actual device. Used for anonymous authentication and quota tracking.
Conversion History
Currency pairs, amounts, and timestamps. Stored locally on your device only - never transmitted to our servers.
AI Scanner Images
Images you capture for price scanning. Transmitted securely (HTTPS) to our servers and analyzed with Google Gemini AI. Images are stored only temporarily while being processed and are deleted automatically within 30 minutes.
App Preferences
Theme, number formatting, and display settings. Stored locally on your device only.
Usage Quotas
Number of AI scans and OCR sessions used. Synchronized with our servers for quota management (free: weekly reset, Pro: monthly reset). Quotas are tracked per anonymous device ID.
2. Information We Do NOT Collect
We explicitly do not collect:
- Personal names or contact information
- Email addresses
- Phone numbers
- Precise location data (GPS)
- Browsing history
- Data from other apps
- Social media profiles
- Financial information (payments handled by Google Play)
3. Third-Party Services
The App integrates with the following third-party services:
| Provider | Purpose | Data Shared |
|---|---|---|
| Google Gemini AI | AI image analysis for price scanning | Image bytes, target currency code, user's language preference |
| Google Play | Subscriptions and payments | Google manages all payment info - we never see card details |
| Google AdMob | Non-personalized advertising (free users only) | Ad requests, device type, general location (country). No personal data is shared. Pro users see no ads. |
| Firebase Analytics & Crashlytics | App analytics and crash reporting | Anonymized usage events, app performance metrics, crash logs. No personal identifiers. |
| api.currency.wiki | Exchange rate data | Currency pair requests only (no user identifiers) |
| Wearable Data Layer | Wear OS Data Layer API | Exchange rates, currency preferences synced to paired watch only |
4. Analytics and Advertising
We use limited analytics and advertising services to improve the app and support free users:
Analytics Services
- Firebase Analytics - anonymized usage patterns to improve the app experience
- Firebase Crashlytics - crash reports to fix bugs and improve stability
Advertising (Free Users Only)
- Google AdMob - displays non-personalized interstitial and rewarded ads
- Ads shown periodically based on engagement (not content-targeted)
- Global cooldown prevents excessive ad frequency
- Rewarded ads are optional - watch to earn bonus AI scans
Pro subscribers enjoy a completely ad-free experience with no advertising SDK active.
We do NOT use personalized advertising. Your data is never sold or shared for targeted advertising purposes.
8b. Widgets and Watch Sync
Home screen widgets and Wear OS watch tiles:
- Widgets read cached exchange rate data stored locally on your device
- Widget configuration (currency pairs, display preferences) is stored locally
- No additional data is transmitted when widgets refresh - they use locally cached rates
- Wear OS sync uses the Wearable Data Layer API to transfer exchange rates to your watch
- Watch sync only occurs when your phone and watch are paired via Bluetooth
Data synced to watches includes: base currency, favorite currencies, exchange rates, daily change percentages, and your number format preferences. No personal data is transmitted.
10. GDPR & CCPA Compliance
For EU Users (GDPR)
You have rights to access, rectify, erase, restrict, and port your data. Our legal basis is legitimate interests (anonymous authentication), contract performance (providing features), and consent (AI scanning).
For California Users (CCPA)
We do not sell personal information. California residents may request disclosure of data collected and request deletion.
Right to Access
Request a copy of all data we hold
Right to Delete
Request complete deletion of your data
Right to Portability
Export your data in a portable format
Right to Opt-Out
Choose not to use features that transmit data
11. Contact Us
For privacy-related inquiries or to exercise your rights:
Support
currency.wiki/support
