I imagine it isn't just a publicity stunt. From what I can guess, this is a multi-facet approach at divesting their core (route-planning) business. I think there are two distinct outcomes from this announcement.<p>1. New tools built from ground up to plan, schedule, and operate buses. I imagine there are a lot of efficiencies to be gained here, and they can probably resell these tools if it is successful. Automated, dynamic schedule, dispatch, even ticketing. There's a lot of old tech to be replaced/improved.<p>2. Integrating the data they gain from their app to find and operate profitable routes. One of the key issues of the London bus system is that people do not "tap off". This means there is limited information about how to best optimise TfL routes. While TfL can sample existing routes and have a good understanding of existing infrastructure, a problem lies in identifying new routes. Citymapper, through its apps, likely has a more intimate understanding of routes that are desirable. They have point to point data - even the data where people walk, as opposed to which stop they get on/off. They also don't have an obligation to serve unpopular routes whereas local governments (might) run buses at a loss in order to be accessible. This enables Citymapper to design and tailor routes specifically to be profitable routes that their customers desire.<p>3. The third outcome is just the outcome of doing both 1 and 2. By building their own bus operating system, they can prove the system themselves and make it even more enticing to potential buyers.<p>I'm very interested to see how this turns out and whether Citymapper will actually end up running real bus routes across London, and potentially other cities.<p>Just think about it - do you ever transfer during your commute? Would you prefer a route with less transfers and walking? This is the type of problem Citymapper can address. They have a wealth of data at their hands and are much less constrained by regulations. That said, there are several good reasons why public transit is almost always subsidised and I hope Citymapper is conscious of that.