Use Your Phone as a Document Camera

A phone is often the best camera in the room. It focuses well on handwriting, handles close-up work better than many laptop webcams, and can move around the classroom. VisualizerApp lets you use that camera in the browser, then freeze, annotate, capture, or present the view from your computer.

Teacher use only: Students should not use Phone Camera. The teacher in charge should operate both devices and avoid showing faces, names or private surroundings unless needed for the teaching activity.

How the phone connection works

1. Open VisualizerApp v3 on the computer, open the left menu, and choose Phone Camera.
2. Scan the QR code with the phone within two minutes. On the phone, choose Start camera and allow camera access. This starts a local preview; sharing waits for approval.
3. Check that the same four-digit code appears on both devices, then approve the phone on the computer within 30 seconds.
4. Choose Data saver, Standard (recommended), or High (strong connection). High uses more battery and data and may not be available on every phone.
5. Wait for the phone feed to appear in VisualizerApp on the computer.

The connection uses WebRTC. It is designed for a direct phone-to-computer camera workflow rather than uploading the camera video to VisualizerApp for normal use. Wireless pairing does need a network connection to set up.

For the most reliable connection, keep the phone and computer on the same Wi-Fi network. Some school networks isolate devices or restrict peer-to-peer connections, which can prevent pairing. If that happens, you can continue with the computer's built-in camera or a connected USB webcam or visualiser.

Capture work or finish sharing

Once the camera is ready, the phone automatically hides the extra settings and leaves a compact dock over the camera preview. The compact dock keeps Show live feed on computer, Capture example, the capture count, Stop sharing camera and More controls within reach. Show live feed returns both the computer and an open Presenter window to the single live phone view without deleting any captured examples. Choose More controls for all options and Camera view to collapse them again.

The full phone controls can Capture example and Undo last capture for up to four examples. Capturing is Free and saves the examples as frozen frames in the computer browser. Done – show comparison prepares the Pro Student Work layout in Presenter Mode; on Free, the captured frames remain available for normal frame navigation and annotation.

When the session is finished, choose Stop sharing camera on the phone. That intentionally ends Phone Camera mode on the computer; choose Start camera there to return to its local camera. If Wi-Fi or mobile data drops briefly, both pages show a reconnecting state and the approved session has up to one minute to reconnect. After that the camera stops and a new QR code is needed. The full controls reopen automatically if the camera needs attention. Do not choose Stop sharing for a temporary interruption.

Cancel or Stop on the computer ends the pairing too. Pairing sends camera video without microphone audio. The receiving computer can capture or record what you show; stopping sharing does not delete those copies. Older v2 Phone Camera links open v3 so you can start a new secure pairing.

When a phone is better

Use a phone when the built-in webcam angle is poor, the writing is too small, or you need to move around the room. It is especially useful for close-up science work, sketchbooks, practical demonstrations, and student work that is easier to bring to the camera than to the front desk.

The trade-off is steadiness. For short demos, holding the phone is fine. For a whole lesson, use a simple stand, clamp, stack of books, or desk mount so the image stays still and your hands are free.

Classroom ideas

• Freeze a clear frame of a worksheet, then annotate it from the computer.
• Walk to a table and capture a student's method; compare multiple examples with the Pro Student Work layout.
• Show a science sample or object from multiple angles.
• Use Pro Presenter Mode when you want a cleaner output for a projector or video call.
• Use non-identifying frame labels. Add a student's name only when needed for the teaching activity and permitted by your school policy.

Tips for a clearer image

Use more light than you think you need. Keep the phone parallel to the page when showing text. If autofocus keeps hunting, wait until the image is sharp and then freeze the frame. Landscape orientation is better for wide worksheets; portrait is better for a single page or book passage.