Many workflows and surveys integrate or are based around a photo or video experience. The use of the devices' built-in cameras is fairly straightforward. There are a few things to keep in mind though.
The first is lighting. Many events take place in darkened areas, so it can be hard to take a good picture without proper lighting. Good indirect lighting sources will make some options easier, like facial recognition, and will look more flattering for the event participants.
All photo apps made in the experience editors will ask if another participant would like to join the screen before the photo is taken. If you press the Add Another Person button, you would be taken to the first screen of the workflow and prompted to either check in or register the participant you are adding to the experience. This can be repeated as many times as you like. All participants who join the photo this way will receive the photo via email or text message.
All photo and video apps have the option of retaking the photo or video after they have finished. This is accomplished by pressing the Retake button on the screen following the photo or video capture screen. Only the most recent photo or video captured will be uploaded to the server and sent out via email or text message to the participant.