"The geographical areas of London and New York are pretty comparable," he continued. "But the data in London is probably a bit harder to work with because it's in a different format to every other city's."
However, Yusuf went on to praise TfL for the amount of live data it offers compared to other cities. This enables Citymapper to introduce a range of live features, such as alerting users to issues on their favourite tube line or showing crosses next to tube stations that are experiencing problems.
"We like the idea of a personalised city whereby we don't care about any disruption," said Yusuf. "We care if it affects you. We're interested in the experience with the individual and the city and how the smartphone empowers an individual to experience their city."
The app has elements of humour built into it that aim to make people's commute a little less painful. For example, when a user asks how to get from A to B a jet pack option is also given, which is in fact based on real jet pack calculations, according to Yusuf. "We like having fun in the space," he said. "Someone's commute is always seen as the worst part of their day and a negative experience. We're trying to change that."
The entrepreneur said he wants to see the app expanded so that it covers every city in the world but revealed that in the short term he would continue to research what data cities have to offer and listen to Citymapper users to see where demand is coming from.
What the investor thinks
Investor at Index Ventures Robin Klein said: "Citymapper is a brilliantly conceived and executed navigation app. We particularly like the fact that unlike the vast majority of apps, Citymapper is an app that people use every day and have on their 'home' screen.
"The real time data across multiple transport methods and the simplicity of use is very powerful.
"We believe Azmat to be a very talented product person and entrepreneur. He has concentrated on deepening the experience rather than rushing to spread it wide across multiple cities, which he will do in time.
"Citymapper has not yet developed its business model but there are multiple potential revenue streams, which it would be inappropriate to discuss now."
Citymapper is also backed by Connect Ventures.
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