Document Camera for Teachers

VisualizerApp is meant for the ordinary classroom moments where you need to show something physical: a worked example, a book page, a student's draft, a science sample, or a quick model on paper. It runs in the browser, so you can start with the camera already in front of you instead of waiting for a specific brand of document camera software.

VisualizerApp is for teachers, tutors and teaching staff to operate, not students. The teacher in charge should operate both devices when using Phone Camera and avoid showing faces, names or private surroundings unless needed for the teaching activity.

Where it fits in a lesson

Use it when the class needs to see your hands, the page, or the object while you talk through the thinking.

• Modelling expert thinking — project worked examples and exemplar work live.
• Whole-class feedback — put pupil work under the camera, tag what you see, and discuss it together.
• Formative assessment — capture mid-lesson understanding and reopen it tomorrow to check impact.

Freeze keeps a good frame on screen while you move the paper away. Annotation lets you underline a sentence, circle a misconception, label a diagram, or draw the next step over a frozen image.

A simple classroom setup

1. Open the current VisualizerApp v3. The older v2 interface remains available if needed.
2. Allow camera access and choose the camera you want to use.
3. Angle a laptop webcam down at the desk, plug in a USB camera, or connect a phone wirelessly if you need a better angle.
4. Use Freeze before you annotate so the image stays still while you explain.
5. Use split view when you want to compare a live page with a captured example.

What to expect

A laptop webcam is enough for quick modelling, but it may need good lighting and a careful angle. A phone camera usually gives a sharper view of handwriting, diagrams, and 3D objects. A dedicated document camera is still nicer for a permanent desk setup because the arm and focus are always ready.

The app's main privacy idea is simple: normal camera processing happens locally in your browser. Your camera feed, frozen frames, and annotations are not uploaded for core use. Optional services such as Pro activation, wireless pairing and book search are separate and explained in the privacy policy. Google Analytics runs only if you allow it in Analytics settings.

If a camera stops working

First check the camera permission beside the browser address bar. Then close Teams, Zoom, Meet, camera software, and other tabs that may already be using the camera. For a USB camera, unplug it, wait a few seconds, reconnect it, and retry with Resolution and Aspect Ratio set to Default.

An Incognito or Guest window is a useful test: if the camera works there, the likely cause is a saved permission, extension, or browser-profile setting rather than the camera itself. The current v3 Hardware panel does not include the older Copy camera diagnostics control. Note the browser/OS, camera model, selected Resolution and Aspect Ratio, build number, and exact error before using Feedback/Bug?. See the full troubleshooting guide.

Good uses to try first

• Model a paragraph edit, maths method, or diagram label under the camera.
• Freeze a pupil's answer and annotate strengths or next steps.
• Record a short spoken teacher note on a captured piece of work so a pupil can hear feedback in your voice.
• Save selected annotated frames in Lesson Decks to reopen in a later lesson; Free keeps two saved decks and Pro removes that count limit.
• Use the timer and camera together for group tasks or short practical work.
• Open a PDF or resource beside the camera when you want reference material on screen.