dated: 8 September 2026
App: Calvora (net.stackova.calvora)
Contact: stackova7@gmail.com · https://stackova.net
Calvora is a mental math practice app. We designed it to keep as much data as possible on your device.
1. Data stored on your device
Scores, coins, theme, language, sound, reminder times, and practice history stay in local app storage on your phone. This data is not uploaded to Stackova servers. You can remove it by clearing app data or uninstalling Calvora.
2. Permissions
Internet — load optional ads and open privacy / store links.
Network state — avoid requesting ads when you are offline.
Vibrate — optional haptic feedback after answers (you can turn this off).
Notifications — optional practice reminders you schedule in the app.
Boot completed — restore those reminders after a device restart.
Advertising ID — used by Google AdMob when ads are enabled, subject to your device ads settings.
Calvora does not request access to photos, files, contacts, location, microphone, or camera.
3. Advertising
The free version may show Google AdMob banners, interstitials, or rewarded ads. Google and its partners may collect device identifiers (including Advertising ID), coarse location derived from IP, and interaction data to serve and measure ads. You can learn more and opt out in Android settings under Privacy / Ads, and in Google’s policy:
https://policies.google.com/privacy
https://policies.google.com/technologies/ads
Where required, Calvora shows a consent form (Google User Messaging Platform) before personalized ads.
4. Children
Calvora is a general-audience education app. We do not knowingly collect personal information from children. If you are a parent and believe a child provided personal data, email us and we will help you remove it from any third-party ads profile we can reach.
5. Sharing
If you share a result, Android’s share sheet sends only the image or text you chose to the app you pick. Stackova does not receive that share.
6. Security
Practice data never leaves the device except through ads SDKs described above. We do not operate a Calvora account system.
7. Your choices
Turn off sound, vibration, and reminders in Settings.
Deny notification permission; the app still works.
Limit ad tracking in system settings.
Uninstall the app to delete local data.
8. Changes
If this policy changes, we will update the date above and the in-app privacy link.
9. Contact
Stackova
Email: stackova7@gmail.com
Web: https://stackova.net