In the period 2007-2009 I was a heavy user of Dopplr, a geographic context tool. You’d add your upcoming trips to it, “I will be in Zurich January 4th”, and share it with your network “Your contact E.R. will also be in Zurich that day, and your contacts A.G., H.G. and A.A. live there.” This was helpful to spot potential face to face meet-ups with those people in your network you’d normally not bump into. It was a geographic serendipity tool, and it helped me meet up with people in my network regularly enough to make it worthwile to add my trips to Dopplr. For instance it enabled having a beer with Thomas (his and my photo of that moment). In 2007 I wrote about how Dopplr played a role in my digital routines, and in 2009 how I liked it as a contextual tool that, although geography based, doesn’t use maps.
In 2009 Dopplr was acquired by Nokia, and similar to other useful tools Nokia bought (such as Plazes), it was then phased out. At some point (June 2013) I deleted my account, which by then had been dormant for a long time, after downloading all my data.
Now the domain Dopplr2.com is active (the original dopplr.com domain now hosts a site looking at legal aspects of current news) and promises to relaunch a similar service. It uses the same colors as the logo of the original Dopplr, so I will be curious to see what they offer when they launch.