ABC is adding a simple button to its iPhone and iPad app that changes the functionality offered in a huge way. A new "Live" option will allow users in certain cities to watch their local channel in the same way they would from a TV, according to a report from the New York Times

For the time being, the only areas supported will be New York City and Philadelphia, but the Disney-owned company plans to launch the service in the six other cities in which it owns stations sometime later this summer. It is also talking to its 200 affiliate stations to bring the streaming feature to the content aired there as well.

ABC has already worked out a deal with Hearst, which runs affiliate stations in 13 markets including Boston and Pittsburgh. The broadcaster expects the "live" functionality to be available there within the coming months. 

The stream will only be available for users paying for a cable or satellite subscriptions, which seems a little odd because local ABC channels are available free with an over-the-air antenna. For subscribers though, it gives them a little extra for their money.

ABC actually planned to launch this feature in 2014, but it decided to push it forward a year. It's quite possible that the service offered by the controversial Aereo could have caused it to speed up its plans.

The advertising offered on the mobile app will actually vary from what's served on traditional television. The Nielsen Company is not able to measure viewers on live streaming shows yet, so the ads will be the same sort shown on