MAS provides first-party applications to simplify streaming off of an internet connected device. As a part of the regular setup flow for your match, the application will ask you if you want to connect a camera. Most of the time, you will be using the same device as you intend to stream on so this step will be relevant to you.
You can also do this step again during a match, swapping between multiple cameras and other input sources so its not super important to get this step correct right now. Check the troubleshooting steps if you are having difficulties.
Granting Permissions
You will be asked to grant permissions to use the device's camera and microphone (even if one isn't detected and/or you are plugging in a camera). This is a one off permission. If you intend to use a network camera or if you will be using a different device for A/V capture then you can deny permissions or click Select other input, otherwise please grant these.
Firefox requires this step each time.
See troubleshooting permissions if you are unable to get camera/microphone access.
If you/your device rejects the permission request, or a camera cannot be found, you may get "stuck" on the above permission access request. Please click Select other input or check your device settings to continue.
Onboard Cameras
Tap the Select camera row to display the camera picker. You can shortcut tap on the device you intend to use or tap on Open camera selector.
By default, your onboard cameras will be listed and any networked cameras will be included with (networked) next to them. This does not guarantee that the networked camera is actually online - just that it exists and will be instructed to attach to this match. Check troubleshooting for more help if you select a network camera and no video comes through on the stream.
Camera Selector
The camera selector can be brought up to provide more fine-grained control over any selected camera. Note, this is mostly just relevant for onboard cameras, devices plugged in over USB, or PTZ controls on networked cameras are better controlled on these devices native interfaces directly.
Where available, the camera selector will let you control the zoom level ( / ), camera light () and which device () is selected. Not all devices support this and will be greyed-out/disabled accordingly (in the above example, zoom and light are unavailable).
You can come back to this at anytime, including when the match is underway and tweak these settings. When a camera on your device is working, many platforms will have a red or green icon letting you know that it is enabled (usually at the top of your screen).
Networked Cameras
Sometimes, you will want to use a camera on a different device than the you are setting up a match. Perhaps you have a camera connected to the internet (such as an IP/CCTV/RTMP camera) or you are looking to work with multiple cameras at the venue.
In this case, your admin can define networked cameras on their backend, and these will appear in the Scoring App under the camera selector.
When you select one of these networked cameras, the MAS server will start listening to this device for video, rather than waiting for you to send it video.
Screen Recording
It is possible to use the screen recording feature available on Web and some 
Android devices to record a video from another tab. You may wish to do this for analysis purposes, or to augment your livestream with another feed.
Some devices, like modern 
Chrome, will also allow you to capture audio from a window/tab - but you will otherwise need to select another audio source.