Privacy | Cognitive Card Games

Last updated: April 28, 2026

This Privacy Policy explains what information X² Challenge (the “App”) collects, how it is used, and your rights regarding your data. By using the App, you agree to this policy.

The App is provided by Cognitive Card Games LLC (“we,” “us,” or “our”), St. Louis, MO 63119, United States.

Who this policy covers

This policy applies to the X² Challenge mobile application on iOS and Android.

What we collect

X² Challenge offers two ways to play:

Guest mode. If you play as a guest, we do not collect any personal information. The App keeps your game state on your device and does not transmit it anywhere.

Classic mode with a saved account. If you create a Classic-mode account so your score persists across devices, we collect and store only:

A username you choose. You pick it; it does not need to be your real name or contain any identifying information.
A cryptographic hash of the 4-digit PIN you set. We never store the PIN itself. We store only a hash derived from it, and use that hash to verify sign-in attempts.
Your game score.

We do not collect your email address, phone number, device identifiers, advertising IDs, location, contacts, photos, or any other personal information.

How we use your information

We use the username and PIN hash solely to authenticate you when you sign in. We use your score solely to restore your progress when you sign in on a new device. We do not use your information for advertising, marketing, profiling, or sale to third parties.

Where your information is stored

Account data (username, PIN hash, score) is stored in a Postgres database hosted by Supabase, which runs on Amazon Web Services infrastructure in the United States. Supabase acts as a data processor on our behalf and is contractually required to protect user data.

Data sharing

We do not sell your personal information, and we do not share it for marketing, advertising, or analytics purposes. We share data only:

With Supabase, our database host, solely to provide the account and score-saving features described above.
When required by law, such as in response to a valid legal process, court order, or government request.
In connection with a business transfer, such as a merger, acquisition, or sale of substantially all of our assets. In that case your data would continue to be protected under this Privacy Policy or an equivalent one, and we would notify you of any material change.

Data retention and deletion

We retain your account data for as long as your account exists.

You may reset your PIN from within the App at any time, which replaces your stored PIN hash and resets your score to zero.

If you want your account and all associated data deleted, contact us at peterblakey@att.net and we will remove your data from our database within 30 days.

Children’s privacy

X² Challenge does not knowingly collect personal information from children under the age of 13. If you believe a child under 13 has created an account, please contact us at peterblakey@att.net and we will delete the data.

Security

We take reasonable technical and organizational measures to protect your information, including cryptographic hashing of PINs and encrypted transport (HTTPS) when your device communicates with our database. No system is perfectly secure, but we handle your data with care.

Your choices

Play without an account. Use Guest mode to avoid any data collection.
Delete your data. Email us at peterblakey@att.net and we will delete your account.

Changes to this policy

We may update this Privacy Policy from time to time. When we do, we will change the “Last updated” date at the top of this page. Material changes — such as newly collecting data types we did not previously collect — will be communicated through the App before they take effect.

If you have questions about this Privacy Policy or wish to request deletion of your data:

Email: peterblakey@att.net