Privacy Policy

Deduce is built to be played with as little personal data as possible. You can play fully anonymously; signing in is optional and only exists to save your streak across devices.

Last updated: 3 August 2026.

What we collect

• Anonymous play. When you first open Deduce we set an anonymous session cookie so we can track your streak and which puzzles you've solved. This is not tied to your name or email.
• Gameplay data. Your attempts, solve times, scores and streaks — needed to run the game, the leaderboard and your streak.
• Optional sign-in (Google or email). If you choose "Save your streak", we store a stable account identifier and your display name and email — only to link your progress to a durable account (and, for the eBook, to deliver your PDF). With Google sign-in we receive a verified token, never your Google password; with email sign-in we use one-time codes, no password at all.
• Payments (if you buy). Pro and eBook payments are processed by Razorpay under its own privacy policy — we never see or store your card or UPI credentials. We keep your subscription status and transaction identifiers so we can grant what you paid for, handle refunds, and meet tax rules.

How we use it

• To generate and validate the daily puzzle, score it fairly, and rank the leaderboard.
• To keep your streak and history, and to merge your anonymous progress into your account if you sign in.
• To understand—in aggregate—how the game is used so we can improve it.

What we don't do

• We don't sell your personal data.
• We don't run third-party advertising.
• We use product analytics (PostHog) to understand how the game is used — events like "puzzle started" tied to a random visitor identifier stored in your browser, and session replays of in-app interactions to find usability problems. Analytics data contains no puzzle solutions and is never sold.

Google & YouTube API Services

Deduce uses Google API services in two limited ways:

• Google sign-in (optional, described above) — used only to save your streak to a durable account.
• YouTube uploads (our own channel). Deduce's internal publishing tool uses YouTube API Services to upload our videos to our own YouTube channel (@deducepuzzles). It acts only for the account that explicitly authorizes it (scope: manage your YouTube videos) and touches no other user's YouTube or Google data.

Deduce's use of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements. Use of YouTube API Services is also governed by the YouTube Terms of Service and the Google Privacy Policy. You can revoke Deduce's access to your Google account at any time via your Google security settings.

Data retention & your choices

You can play without an account and clear the cookie any time via your browser. To request deletion of an account (Google or email sign-in), contact us (see below) and we'll remove the associated account and gameplay records; transaction records we're legally required to keep (tax/accounting) are retained for the statutory period only.

Contact

Questions or data requests: get in touch.