Tag certain riders

I’d love to be able to “tag” certain riders in a group ride and have them more visible during the ride. E.g some kind of thing above their head like the ride leader has but a different colour. Particularly in large group rides where you all get put in the same kit I’d like to be able to keep an eye on a few of my mates who I’m trying to beat

I like this idea. It would also facilitate meetups, for times when you’d like to ride with your group of friends, but during an event.