MathNinja Privacy Policy

Effective September 28, 2026

MathNinja is a math practice game for children, made by Ariel De Prada. This policy explains what the app does with information. The short version: nothing leaves the device.

What the app collects

Nothing. MathNinja does not collect, transmit, sell or share any personal information. It has:

• no accounts or sign-in
• no advertising
• no analytics or tracking
• no in-app purchases
• no chat or social features
• no third-party code that collects data
• no internet access: the app never goes online (on Android it doesn’t even request the internet permission)

What the app stores on the device

To pick which math facts to practise next, the app keeps a progress file on the device itself:

• which math facts have been answered, whether each answer was right, and how long it took
• which stages have been cleared, and the best time for each
• the ninja colour picked on the menu, and whether a parent turned on “unlock all stages”

This file never leaves the device. We cannot see it, and it is not linked to a name, email, device ID or any other identifier.

Deleting the data

• Parents screen: on the menu, hold the Parents button, then tap Reset all progress.
• Uninstall: removing the app deletes the progress file.

Children’s privacy

MathNinja is made for children aged 7 to 10. Because it collects no personal information from anyone, it collects none from children under 13, in line with the Children’s Online Privacy Protection Act (COPPA).

Changes to this policy

If the app ever changes how it handles information, we will update this policy and its effective date before releasing that version.

Contact

Questions about this policy: luyikao@hotmail.com