A margin big enough.
Write, Draw, Create by hand on iPad. Let us translate and connect to the digital world.
02
Your notes, papers and LaTeX, in the apps you already use.
Write a proof by hand. Each line is typeset in LaTeX beside it as you finish it.
Sketch a system. Claude and ChatGPT read the page through MCP and suggest a change; you accept or remove it.
Draw a brand. Your LLMs see the marks and the palette and leave their feedback as a suggestion.
Start for free, and upgrade as your workflow grows.
Get started with the essentials.
$0.00
Get startedFor students who want to do more.
$9.99/ month
$99.99/ yearSave 17%
For labs, departments and teams.
Contact usNot sure? Start with Free. You can upgrade anytime.
Plain answers about what Corollary does.
Corollary is an iPad app for people who write mathematics. You write and draw by hand with Apple Pencil, and each line is typeset in real LaTeX beside your handwriting. Your notes are searchable, connect to the apps you already use, and can be read by Claude and ChatGPT through MCP.
Yes, if you let them. Corollary runs an MCP (Model Context Protocol) server, so Claude, ChatGPT and other MCP apps can read and search the folders you choose. Access is off by default and set per folder. Anything an AI writes arrives as a suggestion, labelled with its name, that you accept or remove.
There is no chat inside Corollary: you use the AI you already have. AI access is part of Pro.
On your iPad first. Without an account, everything stays on your device. With Pro, your notebooks sync to Corollary’s cloud storage, and you can keep copies in iCloud Drive, Google Drive or Dropbox. You can export your work at any time (PDF and PNG on Free; .tex too on Pro) and delete your account and its data whenever you want.
On iPad with Apple Pencil, which is where you write. The Mac and iPhone apps open the same notebooks so you can review, typeset and export them.
Think freely. Work precisely.
Proof. Write it the way you think it: crossed out, redrawn, in the margin. Keep the precise version beside it, in real LaTeX, in files that are yours. Claude and ChatGPT can propose; only you accept.