Wikipedia
Hailo
Hailo is a British technology platform that matches taxi drivers and passengers through its mobile phone application. Founded in London in 2011, the Hailo taxi service is available in 16 cities (as of December 2013).
As of May 2013, Hailo has enabled more than 3 million rides for passengers from over 30,000 registered taxi drivers.
The Hailo Passenger App is available as a free download from the App Store and Google Play for both iOS and Android devices.