Privacy Policy

1. Who this covers

This policy applies to the Chalk apps for iPhone and iPad, the Chalk web app at trychalk.me, and this website. It covers two kinds of people: learners, who ask Chalk questions and work through lessons, and tutors and educators, who write lesson plans and review how their learners are doing.

Chalk is currently in beta. Where a section below describes something that is still limited, it says so rather than describing an end state we have not built.

2. What we collect

Your account

Accounts are handled by Firebase Authentication. Depending on how you sign in we receive an account identifier and, where the provider supplies it, your email address, display name and profile picture. On iPhone and iPad you can start using Chalk without signing in at all, which creates an anonymous account tied only to that installation. If you later sign in with Apple or Google, that anonymous account is upgraded in place so your existing work is not lost. If you use Sign in with Apple and choose to hide your email, we only ever see Apple's relay address.

What you ask, and what Chalk draws

We store the questions you send, the lesson Chalk generates in response, and everything it writes on the board, so that your sessions are still there when you come back and Chalk can pick up where it left off. Each stored turn contains your question, the drawing instructions Chalk produced, and its status.

Photos of problems

On iPhone and iPad you can point the camera at a problem. The text is extracted on your deviceusing Apple's built-in text recognition, and only that text is sent to us. The image itself is not uploaded and we never receive it.

Voice

If you talk to Chalk, the audio clip is sent to our server and passed to OpenAI to be transcribed, and the transcript is used as your question. We do not retain the audio after transcription. Chalk's spoken narration is generated the same way, from the text it is about to say.

Handwriting

On iPad you can write your working directly on the board. Your ink is always kept on your own device so it stays on the board between sessions. When you hand an answer in, an image of that ink is also sent to us so the model can read what you actually wrote and mark it, because text recognition alone is not reliable on handwritten maths.

That image is only stored on our servers when you are working through a lesson a tutor assigned to you, so that the tutor can review your work. For ordinary practice on your own, the image is used to produce the response and not kept.

Lessons and progress

If you are a tutor, we store the lesson plans you write. If you invite someone by email, we store that address so the invitation can be claimed. If you are a learner working through an assigned lesson, we store how far through the plan you are and which step each of your turns belongs to.

Subscriptions

Subscriptions are handled by RevenueCat together with Apple. We receive whether your subscription is active, which plan it is, and when it expires. We never see your card details, which are handled entirely by Apple or by RevenueCat's billing provider.

The waitlist

If you join the waitlist on this site we store your email address, along with the page that referred you and your browser's user agent string. That is used to contact you about access to Chalk, and nothing else.

3. What we use it for

• Generating lessons, narration and marking, which is the product itself.
• Keeping your session history so you can return to a board and continue it.
• Showing a tutor how their assigned learners are progressing.
• Checking whether you have an active subscription.
• Keeping the service working: diagnosing errors, preventing abuse, and security.

We do not use your work to advertise to you, and we do not build profiles of you for anyone else.

4. AI models, and training

Chalk generates its teaching using large language models run by Anthropic, OpenAI and Google, reached through Vercel's AI Gateway. To answer your question we send the model your question, the relevant history of the current session, and a description of what is currently on the board. Where you have handed in handwritten work, the image of that work is included so it can be marked.

We use these providers through their business APIs, under terms where your content is not used to train their models. We do not train any model of our own on your work either.

5. Who else touches your data

We do not sell your personal information and we do not share it for advertising. We use the following service providers to run Chalk, and each only receives what it needs to do its job:

If you are working through a lesson assigned to you, the tutor who assigned it can see your progress, your answers, and the handwriting you submitted for that lesson only. They cannot see any of your other sessions.

We may also disclose information where the law requires it, or to protect the rights and safety of our users. If Chalk is ever acquired, information may transfer as part of that, and this policy would continue to apply until you were told otherwise.

6. Where your data is stored

Chalk is built in Canada, but our servers and database are hosted in the United States. Our AI, hosting and payment providers may also process data in the United States and elsewhere. If you are outside the United States, using Chalk means your information is transferred there, where different privacy laws apply and where it may be accessible to authorities under those laws.

7. How long we keep it

Sessions and lessons are kept until you delete them or until you delete your account. Deleting a session removes its turns, including any handwriting stored with it. Deleting your account removes your sessions, lessons and assignments.

Some records outlive that on purpose: we keep subscription records for as long as we need them for tax and accounting, and backups take a short time to cycle out. Waitlist entries are kept until you ask us to remove you.

8. Your choices and your rights

You can delete individual sessions from inside the app at any time. To get a copy of your data, correct it, or delete your account entirely, email us at osoyelowo@mun.ca and we will action it.

Depending on where you live you may have additional rights, including the right to access, correct, delete or export your information, to withdraw consent, and to complain to a regulator. In Canada that is the Office of the Privacy Commissioner. We do not charge for any of this and we will not treat you differently for asking.

You can also use Chalk on iPhone or iPad without an account at all, which limits what we hold to the work itself.

9. Students, and people under 18

Chalk is built for students, so this matters more here than it does for most products. You must be at least 13 to create a Chalk account on your own. We do not knowingly collect information from children under 13.

Where a school, tutor or parent sets up Chalk for a learner, they are responsible for having the authority to do that, including any consent required for a learner under the age of majority where they live. A tutor who invites a learner to a lesson can see that learner's work on it, which is the point of the feature, and should make sure the learner and, where relevant, their parent understands that.

If you believe a child under 13 has given us information, email us and we will delete it.

10. Security

Traffic to Chalk is encrypted in transit, requests to our API require a valid signed-in token, and access to lessons and sessions is checked against the account that owns them. Our database and backend credentials are held in managed secret storage rather than in the application.

No service can promise perfect security, and we are not going to. If we ever discover a breach affecting your information, we will tell you and the relevant regulator as required by law.

11. Changes to this policy

When we change this policy we will update the date at the top. If a change materially affects what we do with your information, we will tell you in the app or by email rather than quietly editing this page.