privacy policy

Effective November 13, 2026

Nerdi (nerdi.app) is a shelf of learning games for children, run by Decision Trees Inc. ("Nerdi", "we", "us"). This policy explains what we collect, why, who we share it with, and the choices you have. The short version: children never sign in or give us anything. We keep a grown-up's name and email if they make an account, and we don't sell personal information or show ads.

1. children

Nerdi is made for children to use with a grown-up nearby. We do not knowingly collect personal information from children, and the games are built so that they don't have to give us any:

children never create accounts, sign in, chat, or type in a name or email;
game progress, favourites and the "jump back in" list are saved only in the browser on your device (its local storage), not on our servers;
the games don't load ads, analytics or any other third-party code;
the guide voices in our games were generated by AI and recorded in advance. Nothing a child does in a game is sent to an AI service.

If you believe a child has given us personal information, email hello@nerdi.app and we will delete it.

2. the microphone (Lantern Isle only)

Lantern Isle can listen to a child read a word aloud, but only after a grown-up turns this on in the game's grown-ups corner. It listens only while the read button is held. A small speech model runs on your device to check the word. The sound is never recorded, stored, or sent to us or anyone else. No other game uses the microphone.

3. what we collect from grown-ups

Account details. When you sign in with Google or Apple, we receive and keep your name, your email address (or Apple's private relay address), and an account ID from that provider. We also record when you signed up and last signed in. We never receive your Google or Apple password.
Subscription details. If you subscribe to Nerdi Unlimited, Stripe handles the payment. We keep your Stripe customer and subscription IDs, your plan (monthly or yearly), its status and its renewal date. We never see or store your card number.
Site analytics. On the site's pages (not inside the games) we use Google Analytics to count visits: which pages are viewed, roughly where from, and on what kind of device and browser. Google Analytics uses cookies and a random identifier for this. Its advertising features and Google signals are switched off, and we never send it names, emails, or anything a child types or says.
Server logs. Like any website, our servers record technical details of requests (such as IP address, browser type, the page requested and the time) to keep the site secure and working.

4. how we use it

to sign you in and keep you signed in;
to check whether your account can play every game, and to manage your subscription;
to answer you when you contact us;
to understand which pages and games people find, so we can improve the shelf;
to keep Nerdi secure, prevent abuse, and meet legal obligations.

We don't sell or rent personal information, we don't share it for advertising, and we don't build advertising profiles.

We share personal information only with service providers that help us run Nerdi, and only for that purpose:

Google and Apple, to sign you in, if you choose them;
Stripe, to take payments and manage subscriptions. Its own privacy policy applies to the payment details you give it;
Amazon Web Services, which hosts our servers and database in the United States;
Google Analytics, for the page counts described above;
internal tools our team uses to run the business, such as Slack. We use it, for example, to see when a new grown-up signs up or subscribes.

We may also disclose information if the law requires it, to protect the rights and safety of our users or others, or as part of a merger or sale of the business. If that happens, this policy will continue to apply to your information.

6. cookies and local storage

Necessary cookies keep you signed in and protect forms against forgery. The site can't work without them.
Analytics cookies come from Google Analytics, on site pages only. You can block them with your browser's settings or Google's opt-out add-on; Nerdi works the same without them.
Local storage holds game progress and favourites on your device. Clearing your browser's site data removes it.

7. how long we keep it

We keep account and subscription details while your account exists. If you ask us to delete your account, we delete it within 30 days. Records we must keep for tax, accounting or legal reasons are kept as long as the law requires, and Stripe keeps its own payment records. Server logs are kept for a limited period and then deleted.

8. your choices and rights

You can cancel a subscription at any time from your account.
You can ask for a copy of your personal information, ask us to correct or delete it, or delete your account, by emailing hello@nerdi.app from the address on the account.
Depending on where you live (for example California, the EU or the UK), you may have further rights: to know what we hold, to object to or restrict some uses, to data portability, or to complain to your local data-protection authority. We'll honour these requests as the law requires, and we won't treat you differently for making one.

9. security

We use encrypted (HTTPS) connections, encrypted database connections and storage, and limited staff access. No service is perfectly secure, but we work to protect your information. If a breach affects you, we'll tell you as the law requires.

10. where your information is stored

Nerdi is run from the United States, and your information is stored and processed there. If you use Nerdi from elsewhere, you understand that your information will be transferred to the United States.

11. changes to this policy

If we change this policy, we'll update the date at the top. If a change is significant, we'll also tell account holders by email or on the site before it takes effect.

12. contact us

Decision Trees Inc.
Email: hello@nerdi.app