Underground users at a north London station can now access 4G and 5G high speed mobile coverage.
Commuters at Camden Town will now have full use of their smart phones to check emails, make calls and stream videos - with other nearby stations to follow.
All four mobile network operators - Three UK, EE, Vodafone, and Virgin Media O2 (VMO2) - are taking part in the rollout.
The eastern section of the Jubilee line between Westminster and Canning Town, the Northern line between Archway and Kentish Town and the Central line between Holland Park and Queensway already have 4G.
Within the next fortnight, customers using Mornington Crescent station will also benefit.
Later this summer Oxford Circus and Tottenham Court Road will get coverage for the first time, along with further stations along the Northern and Central lines.
Simon Pitkeathley, chief executive of Camden Town Unlimited, said it was a "boon to small business".
He added: “That Camden Town is now looped into this evolving scheme will be of great benefit to Camden’s business community and shows TfL leading the way in adoption of technology for all.”
The project is being delivered for the Mayor of London and TfL by BAI Communications, as part of a wider project to bring high-speed mobile coverage to the entire Tube network.
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