Privacy policy

Last updated: September 28, 2026

Hidden Sums is a math puzzle game for children and families, made by Savi Solutions, LLC ("we"). This policy covers the Hidden Sums app on iPhone and Android.

The short version

We don't collect, store or share any personal information from anyone who uses Hidden Sums, including children.

What the app does and doesn't do

• No accounts. There's no sign-up or sign-in, and the app never asks for a name, email, age or any other personal detail.
• No ads, analytics or tracking. The app contains no advertising, no analytics or crash-reporting services, and no third-party code that collects data.
• Progress stays on your device. Your rounds, stars and settings are stored only on the device. We never receive them, and they're deleted if you delete the app.
• No network use of its own. The app doesn't send anything over the internet. The only exception is the optional purchase, described below.
• No links out. The app contains no links to websites or social media.

Purchases

Hidden Sums offers one optional purchase that unlocks every round. It's handled entirely by Apple's App Store or Google Play. We never see your name, Apple Account, Google Account or payment details. The app only asks the store whether the game has been bought, so it can unlock, and that answer stays on the device. Every purchase is behind a parental gate that asks a grown-up to type a number written in words.

Apple's and Google's own privacy policies cover the purchase itself.

Children's privacy

Hidden Sums is designed for children, and is built to collect no personal information from them at all. So there is nothing for a parent to review, correct or delete, and nothing is ever shared with anyone.

Changes to this policy

If a future version of the app changes what it does with information, we'll update this page and the date at the top before that version is released.