Big Screen II is a multimedia application available on iPhone that enables the live transmission and optional recording of video from the device's camera to a second screen via AirPlay. The app does not mirror controls to the second screen or recordings. It offers features such as utilizing the front or back camera, support for landscape or portrait orientation, video and audio recording, camera zooming, tap to focus, double tap to autofocus, exposure adjustment post-focus by sliding, and triple tap to suppress AirPlay warning.

Additionally, users can employ Big Screen II as a document or demo camera, with video recording capabilities at 1280 x 720 pixels using HEVC or H.264 compression. This app is part of a digital whiteboard project developed by the Hines Lab at Cornell University, allowing lecturers to face the classroom while writing on an illuminated glass sheet captured by an iPad camera. The app provides links to instructions for a DIY document camera for videoconferencing lectures and office hours from home.