Crowdsourcing app tracks subway arrival
An independent programmer has taken steps to use technology to improve services in a way city departments haven’t yet achieved. Alex Bell, a graduate student at Columbia University, has developed a free mobile app to track New York City’s subways in real-time.
The app, SubwayArrival, will let commuters know how close the next train is. Bell writes on his blog for the app: “The goal of this project is to provide any user who is connected to the internet, whether through their phone or computer, an instant view of where the subways are throughout the subway system. In addition allow them to click and view when the next train will arrive at a particular stop.”
Bell writes that while a lifelong New Yorker, he became used to Pennsylvania’s punctual regional rail he rode while attending Swarthmore College for undergrad. “And so coming back to NYC where the subways are late by more than five minutes an average of 50% of the time, according to the MTA, is just plain annoying.
“Instead of complaining, I thought, I am an MS Electrical Engineering student at Columbia and I am resourceful, can’t I solve the problem.”
So Bell developed a smartphone app, but one that didn’t require users to actively do anything. Because that just wouldn’t work. Instead, the app uses mobile phone sensing and passive crowdsourcing. The program processes periods of no reception, proximity to subway exits for riders and what cell service tower phones are using, and packages the information for a live map for the website and smartphones.
The app collects and analyzes a phone’s loss of service, a big jump from one cell service tower to another and where a person emerges to figure out which train a person took, where the train had just been and where the train will be. Though the app is always on, Bell designed it to have little strain on a phone’s battery.
The only catch is that a large mass of people — approximately 10,000 users throughout the NYC subway system throughout a day — need to use the app to provide data and thus produce accurate results.
The app is free and available on the iPhone. Bell is working on first a BlackBerry version, then an Android version. Perhaps eager developers will bring the technology to bus systems and other cities — well, the ones that have always tardy trains.