US cable giant Comcast is launching a new over-the-top TV service.

It’s the latest in a string of announcements from platforms and broadcasters alike as they seek to maintain a relevancy with a younger demographic that is moving away from linear television. Showtime and HBO have both made significant announcements in recent weeks.

“With Stream, Xfinity Internet customers can watch live TV from about a dozen networks – including all the major broadcast nets and HBO – on laptops, tablets and phones in their home. It includes thousands of on demand movies and shows to watch home or away and even comes with access to TV Everywhere and a cloud DVR,” said Matt Strauss, Executive Vice President and General Manager, Video Services for Comcast Cable.

Major networks, including the Comcast-owned NBC, CBS, ABC, Fox and The CW are all available.

Stream will make its debut in the Boston market at the end of the summer, before launching in Chicago and Seatle. By early 2016 Stream will be available across the Comcast footprint.

It will be available to Xfinity Internet customers for a monthly $15.