txt bus: wait time information on demand

This paper describes an SMS based text messaging system that delivers real time bus information to users' mobile phones. Many public transit systems provide schedule and fare information on their web sites, and a small subset of these have recently experimented with bus stop countdown displays. In contrast, an SMS based delivery system allows users to receive real time updates wherever they may be. Given that lack of information is an often cited barrier to transit use, particularly among "choice riders" (i.e. those who have access to other forms of transit), such a solution also creates an opportunity for transit organizations to improve their services, thus promoting ridership [6].