The Tally Promise

Every lesson free, forever. No ads, ever. We never sell your child's data.

Tally was started by a parent who wanted their own children to truly understand maths. It is free so that any child can use it. These are the promises we make to every family, and how you can check each one without taking our word for it.

Every lesson free, forever

Every question, every planet and every report is free. There are no in-app purchases, no subscriptions and no locked levels.

How to check: the App Store listing shows no in-app purchases. If that ever changes, the listing shows it.

No ads, ever

Tally shows no ads and has no advertising or analytics code from other companies in it. The app talks only to Tally's own server.

How to check:

• Tally's App Store privacy label says it does not track you.
• Anyone can watch the app's network traffic (for example with a network proxy) and see that every request goes to Tally's own server.
• We publish the list of every network request the app makes and every piece of data our server keeps. Our tests fail if the app makes a request or keeps a field that is not on that list.

We never sell your child's data

We keep as little as we can:

• a nickname, not a real name;
• a school grade;
• what your child does in Tally.

We never ask for a real name, a birthday, a photo or a location. We never sell or share your child's data. The nickname and your email address are encrypted on our server. Before you give consent, nothing about your child leaves the device. You can save a copy, delete your child's data, or withdraw consent at any time, in the app.

How to check: the privacy label, the published data list, and the deletion and export buttons in Grown-ups → Privacy.

The maths is right

Before each release, every question type is checked by two programs written separately, one in TypeScript and one in Python. They generate hundreds of thousands of questions and check:

• every answer;
• every hint;
• every sentence that states a mathematical fact.

We also plant hundreds of deliberate mistakes in a copy of the code. Every one must be caught before a release.

How to check: we publish the method and each release's result. If you find a mistake, tell us (Grown-ups → Quick guide → Report a problem). Each confirmed mistake becomes a new automatic check.

The questions are made with care

Every word a child reads passes an automatic quality check before each release. A reviewer reads each changed question type. A new kind of question reaches children only after a person at Tally has seen it at three levels. A new area of maths is first looked at by an expert.

How to check: we publish the rubric those checks use.

Every year, a report

Each year we publish a short report: how many children learned, what we changed, every mistake we fixed, and any time we did not keep a promise. Research results are published too, including ones that do not go our way.

Questions: support@tallyuniverse.org.