Annotations and Live Broadcasting

Draw, highlight, and write notes on top of any page — like marking up a printed handout, except your students can see it live on their own devices. The killer use case: stop fighting flaky classroom AV by broadcasting your annotations directly to every student's screen.

Drawing on a page

Pick the pen tool from the page toolbar and draw. Your strokes:

Save automatically — no "did I lose my prep work after the bell?"
Reposition with the page layout — when you edit the underlying content, your annotations stay anchored to the right paragraphs
Come in multiple colors and sizes — toolbar lets you pick stroke width and color
Erase precisely — eraser tool removes individual strokes (not pixels)

By default, annotations are personal — only you see them. Great for lecture prep, marking up your own copy of a colleague's content, or working through a difficult problem before showing it to students.

Sticky notes

Drop a sticky note anywhere on a page:

Drag to position
Resize from the corner
Color-code (yellow, pink, blue, green)
Minimize to a small badge when it's in the way
Click to expand again

Useful for:

Marking spots that need revision
Leaving questions for collaborators
Reminders to yourself ("re-record this video before next semester")

Snaps — focused annotations on a region

A "snap" is a snapshot of a specific region of the page that you can annotate separately. Click the snap tool, drag a rectangle around the region of interest, then draw inside it.

Snaps live in their own gallery — accessible from your dashboard's My Snaps page, organized chronologically with thumbnails.

Useful for:

Pulling a small diagram out of context to explain it elsewhere
Comparing before/after of a code refactor
Building up an annotated walkthrough of a specific concept
Saving a question/answer screenshot to discuss later

The original page stays untouched — the snap is a separate annotated overlay.

Live broadcasting — the killer feature

This is where it gets interesting for the classroom.

Your strokes fan out to every student's device in real time

Switch your annotations to broadcast mode during class. Every stroke you draw appears in real time on every student's device — no projector needed, no "can the back row see this?" Students keep your annotations after class for review.

Three broadcast scopes

Class broadcast

Your annotations stream to every student in the selected class. Like drawing on a shared whiteboard. Great for live problem-solving where you walk through a derivation while everyone follows along on their own screen.

Individual feedback

Send annotations to a single student — perfect for personalized feedback on their work. Sit at your desk during a lab, draw corrections on each student's submission, they see it instantly.

Public annotations

Visible to everyone visiting the page, including unauthenticated visitors. Useful for adding errata, hints, or "see also" notes to public lessons.

How fast is live broadcasting?

Latency target: under 100ms in good network conditions
Strokes are streamed via Server-Sent Events (SSE) — pushed to students, no polling
Late-joining students load existing annotations from the database, then start streaming
Works on flaky WiFi (graceful reconnection, no lost strokes)

Per-stroke smoothing reduces visual jitter — the in-flight stroke is smoothed via a moving average before it's sent.

Classroom workflow

A typical live-class flow:

Before class — open the lesson page, pre-mark anything you want to discuss (e.g. underline key terms)
At start of class — switch to class broadcast mode for the right class
During class — draw, highlight, circle as you talk; switch tools / colors as needed
Students follow — on their own device (phone, tablet, laptop, whatever they brought)
After class — students still see your annotations when they revisit the page

The same lesson can be re-used next semester with fresh annotations — your old annotations are scoped per teacher per session, so they don't leak into the new class.

No projector? No problem.

If a classroom has flaky AV, broadcast mode is a hard upgrade: students see your work directly on their device, in their preferred theme, at their preferred zoom level. Especially nice for students at the back of the room, students with vision issues, and remote attendees joining via video call.

Annotation lifecycle

State	What happens
Personal	Only you see; saved to your account
Class broadcast	Streamed to a specific class; saved per-class
Individual	Sent to one student; saved per-student
Public	Visible to all visitors; saved as page-level metadata

You can switch a personal annotation to broadcast (or vice versa) — the strokes stay, the visibility scope changes.

To clear annotations, use the toolbar's Clear option (with confirmation). Cleared strokes are gone — they're not in version history.

Annotations cheat sheet

Goal	Where
Draw on a page	Pen tool in the page toolbar
Add a sticky note	Sticky tool in the page toolbar
Capture and annotate a region	Snap tool in the page toolbar
Switch to broadcast mode	Annotation menu → choose scope (class / individual / public)
Send annotations to one student	Broadcast scope: Individual → pick student
Erase strokes	Eraser tool
Clear all annotations on a page	Annotation menu → clear
Browse all your snaps	Dashboard → My Snaps