You can search for friends on different plattforms. Just enter a username an see what’s happened.
Use “places” to find users in your neighborhood.
You can follow your friends at your Oysterline.
The Oysterline is an ajax-realtime-reader. You will never miss an activity of your friends.
Send messages to the world, all your followers or private to one follower.
Try out the public Oysterline to get a feeling for that.