_Last updated: 24 August 2026
Systa: Learn System Design is an offline-first Android application for learning system design. This policy explains what data the app handles.
Systa does not collect, transmit, or share any personal data. The app works offline, and everything you do — progress, streaks, quiz scores, settings — is stored only on your device. The one exception is advertising. The free version of systa shows ads supplied by Google AdMob, and AdMob collects data as described in "Advertising" below. Purchasing the Pro unlock removes all ads: the ads SDK is then never started and no ad request is ever made.
The app saves the following locally (Android DataStore / app storage) and never sends it anywhere:
Learning progress, quiz scores, streaks, and achievements
App settings (theme, accent color, font, text size, language)
Your Pro entitlement status (whether you purchased the unlock)
This data is removed when you uninstall the app or clear its storage.
systa offers a one-time Pro unlock through Google Play Billing, Payments are processed entirely by Google Play — the app never sees or stores your payment details. Your purchase status is provided by Google Play and cached locally so the app works offline. See Google's Privacy Policy: https://policies.google.com/privacy
The free version of systa shows ads through Google AdMob:
A rewarded ad you can choose to watch in exchange for an extra design-playground run or 24 hours of access to one locked simulator or case study. It is never shown unless you tap to watch it.
An occasional interstitial ad shown after you finish a quiz, at a limited requency.
There are no ads inside lessons, simulators, or the paywall, and no banner ads anywhere.
To serve ads, Google AdMob may collect and process device and usage information, including your device's advertising ID (AD_ID), IP address, and general ad interaction data. This data is handled by Google, not by systa — the app itself receives no personal data from AdMob. See:
Google's Privacy Policy: https://policies.google.com/privacy
How Google uses data from apps that use its services: https://policies.google.com/technologies/partner-sites
In the EEA, the UK, and Switzerland, systa shows a Google-provided consent form before requesting ads, and an Ad privacy settings entry in Appearance lets you change your choice at any time.
Android's system setting Settings → Privacy → Ads lets you delete or opt out of your advertising ID on any device.
Buying the Pro unlock disables ads entirely.
With your permission, the app may schedule local reminder notifications to help you keep your learning streak. These are generated on your device. No notification data leaves your device, and no push service is used.
No accounts, sign-in, names, or email addresses
No analytics or tracking of your learning activity
No location, contacts, or photos
No personal data collected or transmitted by systa itself
(ad data is collected by Google AdMob for free users only — see "Advertising")
systa is a general-audience educational app and is not directed at children under 13. It collects no personal data from anyone. It is not marked as a child-directed app, and its ads are not served under Google's child-directed treatment. systa itself collects no personal data from anyone.
If this policy changes, the updated version will be posted at this URL with a new "Last updated" date.
If you have any questions or concerns about this Privacy Policy, you can contact us at:
Faith Devs
Email: faithdevsinfo@gmail.com