You see all group members on a single map, they also see you when you have enabled the tracking. You can plan a trip with the whole group: place in group points and tracks for easy simultaneous navigation of multiple devices.
In mobile application you are using, look for "Join group" in the ID field enter U or ID or URL of the group (no registration required)
If you have registered, you can join the group via the website
You can add to the group map gpx-tracks or waypoints, they will be downloaded to all group members automatically
If the group type allows allows it, you can control the monitoring on the devices in the group. All at once or individually.
You can add a map of the area, at the entrance and exit system will notify the members of the group, and you can also assign additional scripts