# Sidepaper

> Sidepaper is a paper notebook for iPhone, designed for iPhone Duo. You write by hand, sketch and talk your thinking out on a dot-grid page; boxes, arrows, circles and cross-outs become cards, links, groups and challenges, and your ink is kept exactly as drawn. When a board is done, you tap Done and hand ChatGPT or Claude a short plain-text brief by copy or the share sheet. The reply comes back as suggestions you review.

Tagline: Think on paper. Hand it off when it's done.

## Status

- In private TestFlight testing. Not on the App Store. Coming to iPhone (iOS 18 or later), designed for iPhone Duo.
- Platform: iOS (native SwiftUI app), and a web version at https://sidepaper-web.vercel.app that anyone can use by signing in with Apple or Google. No Android app.
- No price or subscription has been announced.

## What it does

- Write by hand: finger handwriting on a dot-grid page, kept as ink. "Read my ink" turns handwriting and drawn connectors into reviewable notes and links, on device.
- Talk it through: record a spoken ramble; it is transcribed on device and drafted into a board. Each card plays back the moment of the recording it came from. The original recording is kept.
- Sketch to structure: drawn boxes become cards, arrows become links, loops around cards become sections, and a strike across a card becomes a "reconsider" note that challenges it. Suggestions are reviewed; the ink itself is never changed.
- Assistant to board: ask ChatGPT or Claude to lay out a structure (for example a system architecture), share or paste the reply into Sidepaper, and it opens as a board you can correct in ink.
- Done: a Done button marks a board as finished thinking. Its brief opens with "Status: DONE. I've finished thinking this through. Treat these notes as my final decisions, not a brainstorm. Run with it: <request>", with plan, write-up, build and message presets. Editing the board afterwards shows it changed since.
- Structured handoff: select the notes that matter and hand them off as a plain-text brief ("What I'd like:", numbered notes with kinds such as `n1 (question): ...`, and "Links I drew:" such as `- n3 depends on n1`) by copy or the iOS share sheet. Replies come back as suggestions you keep or skip, applied as one undoable step.
- On-device tidying: a small language model trained for Sidepaper (from an open-source base model) labels note kinds (idea, question, claim, task, constraint) and suggests groups. It was trained on practice boards, never on user notes, and runs on the iPhone with no network. Coming with launch; until then, and on older iOS versions, Apple's on-device model is used. Each suggestion is kept or skipped. No remote fallback.
- Standing preferences: when you correct kinds consistently, Sidepaper proposes a habit in plain words (for example "Notes with a date or day are tasks, not constraints · you changed 5 of 5") and applies it only if you accept.
- On the web: the same boards in a browser at https://sidepaper-web.vercel.app. Write with a pen or type, talk it through by dictation (no audio is recorded), tidy, hand off to ChatGPT or Claude, search every board, export a board as an image or PDF, and restore an earlier version. With sync on, the iPhone's boards and ink appear on the web. Photos stay on the device or browser where they were added.
- Sharing: invite someone by the email they sign in with, as editor or view only, and send them the link (Sidepaper emails no one). The link works once, for that email, for 7 days, on the web or iPhone. Text, layout and ink are shared; photos and recordings are not.
- Visible learning: a "What Sidepaper has learned" screen shows learned topics, labelling examples and suggestion acceptance, all removable. Declined suggestions are not offered again.

## Privacy and control

- A Sidepaper account is required once, at first launch. After that, editing works offline.
- Boards, ink, photos and recordings are stored on the phone. Sync is off by default; if the user turns it on, boards and ink (as pen strokes) sync to their own account. A shared board also goes to the people invited to it. Photos and recordings never sync.
- Handoffs contain text only. Ink, photos and voice are never sent to assistants.
- By default there is no account link with ChatGPT or Claude; handoff is copy/paste or the share sheet.
- In private testing (invite-only, not open to the public): connecting assistants that support MCP (for example Claude and ChatGPT) so they can send draft boards to the phone and pick up boards marked Done. The user chooses which boards are visible; only text is shared; replies arrive as suggestions.
- Every AI change is a proposal. Accepted changes apply as one undoable step. A reply to a board that changed after sending is rejected rather than merged.
- Notes drafted from a voice recording are checked against the transcript; notes whose supporting quote, numbers or names cannot be found in the transcript are dropped.

## Who it is for

People who think by writing, sketching and talking: engineers, product managers, designers, marketers and leaders who already use ChatGPT or Claude, especially on iPhone Duo, where the cover display suits quick capture and the inner display gives the board room.

## Links

- Home: https://sidepaper.co/
- FAQ: https://sidepaper.co/#faq
- Web app: https://sidepaper-web.vercel.app