Privacy Policy

You can play anonymously with no account; sign-in is optional and only used to sync your progress across devices.

What we store

Your game stats (XP, streaks, achievements) and, if you buy, your purchase status.

Ads (Google Play app only)

A player who has not bought the full version sees at most three ads a day in the Google Play app, each after a round or a lesson ends. They come from Google AdMob, requested as directed to children, so Google shows no personalised ads and no remarketing. In the EEA, the UK and Switzerland the app asks for consent first, and Settings › Privacy choices changes it. Buying the full version removes the ads.

Ads on the website

The website shows no ads today. When it shows them, they come from Google AdSense, requested with age-restricted treatment, so Google shows no interest-based ads and no remarketing. Third-party vendors, including Google, use cookies to serve ads, and Google’s use of advertising cookies lets it and its partners serve ads to visitors. Google’s Ads Settings turn off personalised ads from Google, and aboutads.info covers other vendors. How Google uses this information: Google’s partner sites policy.

How long we keep your information

• Your account (stats, display name, settings, sign-in, what you own): while you use it. If an account is not used for 24 months and holds no purchase, we delete it. An account with a purchase is kept so that what you bought stays yours. You can ask us at [email protected] to delete any account sooner, and we delete it within 30 days.
• Purchases and refunds: for as long as tax law requires us to keep sales records (at least 5 years). These hold the purchase, not your progress.
• Sign-in links sent by email: Google Firebase sends them, and we keep no copy.
• Passkeys: the public half, with your account, and deleted with it; the private half stays on your phone or computer. When you sign in with one, your network address and the times you tried are kept to limit attempts, and deleted at the first daily clean-up after 2 hours.
• Usage statistics (which days the app was opened, and how a visitor first arrived): stored under a scrambled id that is not your account id, and deleted after 13 months.
• Error reports, performance and lesson progress counts: 90 days.
• Server logs: 30 days.
• Emails we send you (receipts): copies stay in our mailbox as our record of what we sent, for support and tax.

If you are under 13 and a parent asks us to, we delete the child’s information at once.

Children

Before a first sign-in or reminder, the app asks the year a player was born and keeps only whether they are under 13, on the device. A player under 13 is not offered sign-in or notifications. Any player can save with a passkey, which holds no email or name; without it, their progress stays on the device.

Governing law

Math Challenge is operated by Lattice Logic Pte. Ltd. and follows Singapore’s Personal Data Protection Act (PDPA).