I am currently playing around with this iPhone App called Wander. It is a photo-sharing tool that links two people from two cities together. So it's kinda like instagram where you share photos - but you exclusively share it with one other person.
The two people are notified by the application when they are matched. They can either accept the match or reject it. If it's rejected - the app will provide another suggestion the next day. Once they both accept - they become each other's guide for one week.
Being a guide for each other includes completing daily "missions". For example - one of the mission I had to complete is to take a picture from where I was standing. The other mission is to show a picture of what the weather is like from where I live.
From my current experience - my guide and I have been interacting pretty well. We seem to be taking our Guide missions seriously. I'm able to view interesting things from where he lives and I am able to share factoids from Manila.
I strongly recommend for you to try out the App - it's free. Just make sure that when you sign up for it - that you take it seriously. It'd be a shame being a lousy guide.