Why I developed Tube Siren

So last week I was going to get lunch at work. On the way, an idea popped into my head. I'm not going to be so bold as to describe it as a eureka moment or anything, it was just a simple idea. But unlike some of the other ideas I've had, this one seemed like it had a chance of succeeding. The jury's still out on that, but the experiment has begun.

My idea was to come up with a web-based app to allow passengers of London's underground transport system (colloquially referred to as 'the tube') a way of telling each other about delays and crowded stations. Web-based because there was free wifi in tube stations now and the app would work on practically all smartphones. There was no reason to design a native app that needed to be downloaded and installed, though that could certainly be an option in the future. And self-reporting because crowdsourcing seemed like a good way to deal with the problem at hand: crowds.

You see, Tfl (the government authority which controls the tube and publishes official information about it) already does a great job of updating passengers about line suspensions and delays (which can be minor or - the word every commuter dreads - severe). But to date there has been no way of determining whether a station might simply be too busy to travel through. There may well be a "good service" on the line in question, trains may be arriving at a rate of up to one every minute, but they may be arriving full. And the platform you're standing on may also be full. A packed tube train (of eight carriages) carries close to 1,000 people. There could be just as many people, or more, in the station hoping to get on that train when it arrives. When they realise they can't, they wait. As more people arrive.

This happens frequently for short periods of time during the morning and evening rush hours, but over August, because of the presence of the Olympic games in London and the peak of the tourist season, Tfl are expecting the tube to carry more individuals than it ever has done before in its 150-year long history. As such, they're basically asking people not to use the tube at all if possible.

To me, it seemed like the perfect time to launch Tube Siren. Tube Siren is the culmination of the idea I had last Tuesday. It is now the following Wednesday. In eight days I programmed and designed the entire app, set up a dedicated Twitter feed and provoked a response through social media. The BBC's Technology editor, Rory Cellan-Jones, was kind enough to retweet me and spark a lot of interest in the app.

Someone more experienced in programming than me could probably have done it in half the time - the concept and architecture are simple, but the success of the app depends almost entirely on whether or not people make reports on busy stations.

It is contingent on Londoners wanting to spread news about frustrations to their commute in a systematic way. People may have been sending the odd tweet about delays to their journey now and again, but I think the idea of updating a dedicated database offering live monitoring of the tube network is probably a new one. "Tube too busy to travel? TELL LONDON!" - that's how I've introduced the app on the web-page about it (viewable on PCs, not mobile devices). Hopefully people will appreciate that this service is just as much about giving information as it is about receiving it.

This, I admit, is my first foray into crowdsourcing, and at the moment I'm working on spreading the word about Tube Siren to give it the best chance of succeeding. If it does take off, there's always the chance that when the Olympics finish, or when they start charging people to use wifi in tube stations, the popularity of Tube Siren will plummet.

Let's hope not. Anyway, until I see a woeful lack of interest, Tube Siren will be there for all Londoners and visitors to London travelling in those dark little tunnels underground.