A glance is performed with a click on the icon which opens a menu. Listed in the menu are the names of the group members as inactive items.
I've not yet decided how to perform a glance. Either:
- Just by opening the menu and seeing the list of names you do a glance. Being aware of your friends is isomorphic with glancing at them; or
- In the menu, there's an item called 'Glance' (or maybe "I'm OK, you're OK"). This item is selected. The icon should provide a form of visual feedback, maybe by brightening for a minute or two, and the Glance option is subsequently not available for a short period.