Use your phone as a webcam on your computer over WiFi or USB.
DroidCam Webcam (Classic) — description
DroidCam turns your Android device into a webcam.
The app works with a PC client that connects the computer with your phone. Windows and Linux clients are available. Visit www.dev47apps.com on your computer to download, install, and get more info on usage.
Features: - Chat using "DroidCam Webcam" on your computer, including Sound and Picture. - Completely free with no usage limits or watermarks. - Connect over WiFi or USB*. - Microphone noise cancellation. - Use other (non camera) apps with DroidCam in the background. - Keeps working with the screen off to conserve battery. - IP web camera MJPEG access (access camera via a browser or from another phone/tablet/etc).
If you like the app, consider getting the Pro version, DroidCamX, which has: - No Ads. - USB-Only mode for added privacy and security. - Phone calls muting. - 720p/1080p video support via HD Mode. - 'Smooth FPS' option for more stable video. - Pro features on the Windows client including video mirror, flip, rotate, contrast, brightness and other controls.
A bargain compared to actual webcams sold in store!