The request comes up in classrooms, workshops, stand-ups and live demos, and it is always the same shape: one person writes, everyone else watches, nobody else edits. It sounds like a feature every shared editor has. In practice it is surprisingly hard to get without accounts.
Why "just share a doc" doesn't work
A shared document gives you real-time viewing, but its permissions model assumes everyone has an identity. To make students read-only you either invite each of them by email, or you hand out a view link and hope the settings are right — and the first time someone opens it with edit rights, the board is no longer yours.
A paste or screenshot avoids the permission problem by being static, which throws away the reason you wanted a live board in the first place: you are going to keep writing.
One link, two kinds of people
ShareNotes splits the problem along the only line that matters. When you save a note you can add a 4–6 digit PIN and choose what it locks:
- Edit only — anyone with the link can read the note and watch it update live, but typing requires the PIN. This is classroom mode.
- View and edit — the PIN is needed to see the note at all.
So there is one link for everyone. Students open it and read. You open the same link, enter the PIN once, and your browser remembers it on that device, so you are not asked again. Their editor is simply not editable; yours is.
The lock is enforced by the server, not the page. Hiding the editor from students would be cosmetic. Every save is checked against the PIN on the server before it is stored, and only what the server stored is pushed to the people watching.
How the live part works
When you stop typing for a second, your browser saves the note. The server checks the PIN, writes the new version, and sends it to every browser that has the note open, over a WebSocket connection each of them keeps. Students see the change appear without refreshing. Nothing they send over that connection can change what anyone else sees.
Wrong PINs are limited, too: after ten wrong guesses in fifteen minutes, that device is locked out of the note for a while. A presenter PIN is not a bank vault, but it should not fall to a script in a few minutes either.
What we left out, on purpose
- Accounts and rosters. No sign-up for you, no invite list for them. The link is the classroom.
- Student identities. You do not see who is watching. That keeps it usable for a room of strangers at a meetup, at the cost of attendance tracking.
- Chat and comments. A read-only board stays read-only. Questions belong in the room.
And two honest limits. An edit-only note is readable by anyone who has the link, so keep anything private out of it — or use the view lock. And you choose how long a note lives when you save it — no expiry, or 1 hour, 24 hours or 7 days — so a weekly board can stay up while a one-off lesson tidies itself up.
Setting it up in thirty seconds
- Open the editor and write your first line.
- Save, choose Edit only, and set a PIN — six digits if it matters.
- Pick a memorable link such as
sharenotes.dev/physics-10a, or keep the generated one, and put it on the board. Every note also has a QR code for phones. - Keep typing. The room follows along.
The full feature page is classroom mode. If the people watching are your own devices rather than students, a clipboard room is the same mechanism without the PIN.