Privacy

Last updated November 11, 2026. Covers the Sidepaper app for iPhone and iPad, Sidepaper on the web, and this website. Sidepaper is made by Catalyst Logic AI (“we”).

What stays on your phone

• Your photos and voice recordings are stored only in the app on your iPhone. We never have a copy.
• Your boards, notes, handwriting and sketches are stored in the app on your iPhone. Unless you turn on sync, we don't have a copy and can't see them. If you back up your iPhone, they can be part of that backup, under your settings with Apple.
• Organizing runs on the phone: reading your handwriting, turning speech into text, and labelling and grouping your notes. It uses Apple's built-in on-device model or Sidepaper's own small model, which also runs on the phone. Speech is only ever transcribed on the device.
• Writing and organizing work offline.

Your account

You need an account, once, the first time you open Sidepaper. After that, writing and organizing work without a connection. You can create one with Sign in with Apple, with Google, or with a sign-in link sent to your email address. Sign-in is run by Supabase, the service we use for accounts.

For each account we store:

• your email address;
• your name, if you or your sign-in provider share it;
• an account ID.

We use these only to sign you in and to connect the text you send through Sidepaper to your account. Photos and recordings are never stored with your account. Boards and ink are stored with it only if you turn on sync.

If you sign in with Google, we ask Google only for your name, email address and basic profile. We use that only to create your Sidepaper account and sign you in. We don't use it for advertising, we don't sell it, and we don't share it with anyone except Supabase, which runs sign-in for us.

Sync, if you turn it on

Sync is off until you turn it on. When it's on, your boards are kept in your account so they're the same on your phone and on the web: the notes, the links and groups between them, and your handwriting as pen strokes. That includes boards already on the phone. Photos and voice recordings never sync. Each change carries a random ID for the device it came from, so your devices can tell their changes apart. Synced boards are stored by Supabase, with access limited to your own account. Turn sync off any time; deleting your account deletes everything synced.

What goes to ChatGPT and Claude

Only text you choose to send. When a board is done, you pick which notes go. The app shows you exactly what will be sent before anything leaves.

• What's sent: the text of the notes you picked, plus the comments, links and labels attached to them. Ink, photos and recordings are never sent.
• How it travels: through Sidepaper's hand-off server. The server holds the text so the assistant can pick it up and its reply can come back to you as suggestions. Nothing changes on your board unless you approve it. We keep hand-off text only as long as a hand-off needs it. Deleting your account deletes it.
• After it arrives: once ChatGPT or Claude reads the text, the privacy policy of OpenAI or Anthropic covers what they received.
• Copy and share: if you copy the text or use the share sheet instead, it goes straight to wherever you paste or share it. It doesn't pass through us.

Sharing a board

You can share a board by inviting someone by the email address they sign in with. We store that email address with the invite until it's used, cancelled or expires after 7 days. Sidepaper emails the invite link to that address, and emails you when someone asks to join a board you shared, and them when you let them in. These emails go through Resend, our email provider, and carry the board's title, the names involved and the link, never what's on the board. The people on a shared board see its text, layout, links and ink, the comments on it, and each other's names. Photos and recordings stay with the person who added them. You can remove people, they can leave, and you can stop sharing at any time; everyone keeps the copy they have. To report a concern about a shared board, email us.

Boards and notes from ChatGPT and Claude

If you add the Sidepaper connector to ChatGPT or Claude, they can send you draft boards and notes, which wait in your account until your app picks them up, and read boards you send them. If you turn on “Let ChatGPT and Claude see my board names”, they also see each board's name and goal, never its notes. Turn it off any time.

Research, if it's on for your account

Research is offered only to some accounts. When you use it, the text shown on the research screen goes to Sidepaper's server, which asks Google's Gemini to search the web with it. Google's terms then cover what it receives. Nothing else on your board is sent, and the results come back as suggestions for you to review.

Sidepaper on the web

Anyone can use Sidepaper on the web by signing in with Apple or Google. Boards you make there are kept in your account. A web browser can't run the phone's model, so on the web, organizing and drafting from what you dictate run on Sidepaper's own server and model, and the web app says so where that happens. Photos you add on the web are kept in that browser. The web never records audio. On the phone, organizing stays on the phone.

Usage records

While you're signed in, we keep a short record of things that happen in your account, such as signing in or out, a failed sign-in and its error code, a board sent, a reply received, and an assistant connecting. Each record has your account ID, the time and the app version. We use them to keep Sidepaper working and to improve it, and delete them after 180 days. They never include your notes.

What we don't do

• We don't show ads, and we don't sell or share your information for advertising.
• We don't train models on your content, whether ours or anyone else's.
• We don't put advertising or third-party analytics tools in the app. This website uses no cookies, analytics or trackers.

Who helps us run Sidepaper

• Supabase runs accounts and sign-in, and stores synced boards.
• Apple and Google handle sign-in, if you choose them. Apple also delivers the app through the App Store and TestFlight. If you send crash reports or feedback through TestFlight, Apple passes them to us.
• OpenAI and Anthropic receive only the text you send to ChatGPT or Claude.
• Google receives the text of a research request, if you use research.
• Vercel hosts this website, the web app and Sidepaper's server, and keeps standard request logs, such as IP addresses, for security.

We may also share information if the law requires it, or to protect the safety of our users or the public. If Sidepaper is ever sold or merged, this policy will still apply to your information, and we'll tell you.

Deleting your account

Delete your account any time in the app. That removes your account and everything we hold on our servers, including your email, name, account ID, synced boards and any hand-off text. Your boards stay on your phone until you delete them or the app. You can also ask us to delete your data by email.

Security

Data is encrypted between the app and our servers. Account data is stored by Supabase with access limited to your own account. No system is perfectly secure, so we keep as little on our servers as we can.

Your rights

Depending on where you live, including California, the UK and the EU, you may have the right to see, correct, delete or export your personal information, or to object to how it's used. Email us and we'll help, whether or not your local law requires it.

Children

Sidepaper isn't meant for children under 13, and we don't knowingly collect personal information from them. If you think a child has made an account, email us and we'll delete it.

Changes

If this policy changes, we'll update the date at the top. If a change matters, we'll also tell you in the app before it takes effect.

Contact

Questions, or want your data deleted? Email sanjit@catalystlogic.ai.