Deconstructing: MapRoulette

by Chris F

In the next to last OpenStreetMap improvement game that I was able to find till now, MapRoulette. It’s the initiative of OSM member, developer and awesome person Martjin van Exel. It started as an initiative from him to help the OSM US community correct the mistakes that a government data import created to better map the country. It now is one of the most addictive OSM games, from my point of view. Here’s what I think about it.


MapRoulette is a simple game/gamified app. It presents you with a problem and asks you to see if you can fix it. At the moment it asks you to try and connect unconnected roads that apaear that they should be connected (roads that end within 5 meters of another road). When I started working on this round of MapRoulette, there were over 20000 errors that needed fixing, and at the moment there are just under 8000. I started working on it earlier this week, so you can see that it works.

What’s it made of?

MapRoulette works on campaigns: it starts with a type of error that they want to fix (till now only in the US from what I know), and then they allow people to work on it till it’s done. Once no more errors remain, they move to another campaign.


Once on their webpage, as seen above, you’re presented with one of the errors. You are then given options in the right-hand side and can choose to mark the error as a false-positive, if you know it’s not an error or skip it if you think you can’t do it or don’t know if it’s an error or not. If you want to try and fix it, you can open that part of OSM in either JOSM or Potlatch, which are 2 of the 3 big OSM editors out there.


Once you click edit, you get this nice dialogue asking you if you fixed the problem. You have the options to say yes, no, say it was already fixed or that it wasn’t an error after all. The reason why I like ths dialogue is that it allows you to say that you’ve done it or that it wasn’t a problem or that you couldn’t solve it. It’s permissive.

Now comes the best feature of MapRoulette. Once you press any of the buttons, this happens:


and you’re taken to the next problem. Again, and again and again. Once you click that button, there’s no “Do you want to move to the next error”, there’s just “Here’s the next error, have fun”. And that’s what makes it so addictive.

First, all the errors that appear on MapRoulette are easily fixed. Anyone can do it and most of them have the same degree of difficulty. There’s the great option of being able to skip a problem if you want. If you are new to MapRoulette, a guide is always posted on the right-hand tooltip, with an explanation not only of what needs doing, but also why it needs to be fixed. For example, this last connectivity error really helps routing algorythms.

Gamification-wise, it’s interesting to see the statistics of the challenge: how many erros remain, how many have been fixed this day and in the last hour. This helps the players a lot because you know that, for example, from the 24 that have been done in the last hour, 8 are yours.

There are no leaderboards, no levels, no badges. It works completely off the intrinsic motivation, letting them know that they have contributed to getting the number of fixed errors up and lowering the total number of errors, but that’s about it. Another interesting part for MapRoulette is that it works off campaigns, which are another name for missions. Each of the challenges is huge, in the number of hundreds or thousands of errors, so no one person could fix them easily, there’s no solo-ing the dungeon. Instead, it’s a community challenge, and anyone can participate.

As an improvement for MapRoulette, I would like to see the number of original errors, and then the current number, to give me a bigger sense of achievement when I look one week later and see that over 50% of errors have been fixed, and it will also motivate me to work harder to get the number down faster, a progress bar, if you will. I would like to see if it would work better if you also had personal statistics based on cookies, so it could show you the number of the errors that you fixed per session and per day. That might take down the sense of community challenge though, and increase the sense of personal achievement instead of being part of something bigger.

To conclude, MapRoulette is nice and simple, and that’s where it strenght lies.

Chris F.