Chess Master Privacy Policy

Last updated: October 1, 2026

Applies to Chess Master for Android (com.vibetech.chessmaster), version 1.0.7 and later. Published by Vibe Tech LLC.

The short version

Playing against the computer, Lessons, and Puzzle Coach all run on your phone. You don't need an account with us, and we don't show ads. Three things do send data off your phone: the AI Tutor (only when you ask it something), Google Play Games (achievements and leaderboards), and purchases through Google Play. The rest of this page explains each one.

What stays on your phone

Your games, moves, settings, lesson and puzzle progress, and board and piece choices stay on your phone. The chess engine you play against, including the Expert level that comes with Chess Master Pro, runs locally.

When you buy something, Google Play gives the app a purchase receipt. The app keeps that receipt on your phone so it knows what you've unlocked. We don't send it to our server.

AI Tutor

The AI Tutor is the only part of the app that talks to our server. Opening the Tutor screen sends a quick check to see if the service is up, and that check carries none of your data. Nothing else goes out until you type a question and send it.

When you send a question, the app sends three things:

• the current board position, written in standard chess notation (FEN)
• the question you typed
• a random ID the app made on your phone. It isn't linked to your name, email, Google account, or phone number.

That goes to our server, which runs on Render. Our server passes the board position and your question to Google's Gemini AI to write the answer, then sends the answer back to you.

What we keep:

• We don't save your question or the board position.
• We keep the random ID with a count of how many questions it asked today and this month, plus the time of the last question. That's how we enforce the Tutor's limits (currently 40 questions a day and 800 a month). Each ID has one record, and the counts get overwritten rather than stored as a history. We don't delete these records on a schedule. They stay until our server's storage is reset or you ask us to delete them.
• Render, the company that hosts our server, keeps server logs for a limited time set by our plan (up to 30 days). Depending on the plan, those logs can include your IP address. Our own code doesn't log your question, the board position, or your ID.

About Google Gemini: Google uses your question and the board position to write the answer. We use Gemini under Google's free API terms, which let Google keep this content, use it to improve its products, and have people review it. Please don't put personal information in your Tutor questions.

Google Play Games

Chess Master uses Google Play Games for achievements and leaderboards, like total wins and puzzle rating. The app starts Play Games when it opens, so if you've used Play Games before, Google may sign you in automatically without asking. While you're signed in, Google gets your Play Games profile, your achievements and scores, and usage and diagnostic data that Google's Play Games code collects on its own. Google handles that data under its privacy policy (https://policies.google.com/privacy). You can turn off automatic sign-in, or see and delete your Play Games data, in the Play Games app or your Google Account settings.

Purchases

Chess Master costs $1.99 to download. Chess Master Pro is an optional one-time upgrade for $4.99 that unlocks the full Lessons library, the full Puzzle Coach, and the Expert computer level. Boards and pieces are sold separately. Google Play handles every payment, so we never see your card or billing details.

Ads and analytics

There are no ads. We haven't added any analytics or crash-reporting services. The only usage data collected is what Google's Play Games code collects, described above, plus the purchase data Google Play Billing logs for Google when you buy something.

Security

Everything the app sends goes over encrypted HTTPS. The app blocks unencrypted connections.

Who we share data with

We don't sell your data. Tutor questions and board positions go to Google Gemini so it can answer you, and Google may use them to improve its products as described above. Render hosts our server and handles requests for us. Play Games and purchase data goes straight to Google.

Deleting your data

• On your phone: uninstalling Chess Master deletes everything it stored, including the random ID. If you reinstall, the app makes a new one.
• On our server: email freshwaterbruce2@gmail.com with the subject "Chess Master data deletion" and we'll delete any Tutor records we can find for you. Our records are tied only to the random ID, and the app doesn't show you that ID, so we may not be able to match a record to you. Once you uninstall, nothing in our own records can be traced back to you. Render, which hosts our server, keeps server logs that can include your IP address for up to 30 days.
• Play Games: delete your data or turn off automatic sign-in in the Play Games app or your Google Account settings.

Children

Chess Master isn't directed at children under 13.

Changes

If we change how the app handles data, we'll update this page and the "Last updated" date.

Contact

Questions about this policy? Email Bruce Freshwater at freshwaterbruce2@gmail.com.