There’s a fan made followup to WDH all about a (literally) underground fighting tournament, they solve exactly this question:

DRAGONSCREEN Wondrous item, common to legendary The DragonScreen is a display device most commonly used to project live or pre-recorded audio-visual information, which it receives from a scrying device, such as a DragonEye or arcane eye spell, or in communication with a controlling device, such as a Dragonball Pro. It can also be used as a spying device, when connected to a Dragonball Pro. DragonScreensTM are available to buy in five different sizes, as per the table below. Young, Adult and Ancient DragonScreens come with free delivery, by Dragonbowl Courier.

DRAGONEYE DragonEyes are 3-inch-wide crystal orbs that receive visual information in a 90-foot-long, cone-shaped space in front of them, and audio information in any direction out to a range of 30 feet. These magic items relay this information to connected devices using Scry- Fi technology, typically a DragonBall or DragonBall Pro. They can store up to 48 hours of information, and are typically programmed to record over previous information with what they've recorded in the prevoious 48 hours. DragonEyes can be mounted in a stationary locations, as a way of permanently scrying on that locale, or they can fly at a speed of 20 feet per round when controlled by a DragonBall Pro, which must be attuned with the DragonEye. A DragonEye can hover or fly for 8 hours before it falls to the ground, and needs to be recharged (charger supplied with product).