HBO formally unveiled its HBO Now standalone streaming service on Monday, which will be bundled with a newly discounted Apple TV streaming box.

HBO Now will cost $15 per month, and the first month will be free who those who sign up. The service will launch in early April, in time for the debut of the new season of Game of Thrones that will debut in the middle of the month.

"This is a transformative moment for HBO, and we are very excited to launch HBO for you today," said Richard Plepler, the chairman and chief executive of HBO, at what was expected to be the launch of the Apple Watch at an event in San Francisco on Monday.

The service will ship with the Apple TV, which Apple has traditionally referred to as a "hobby". When Apple TV debuted, the price was competitive with other products from Roku and others. Since then, however, devices like the Google Chromecast have dramatically lowered the price. In response, Apple lowered the price of the Apple TV from $99 to $69, Apple chief executive Tim Cook said. That's still far from the price of the $35 Google Chromecast, but more consistent with the $70 that Roku charges for the last-generation Roku 2.

The announcement of the HBO NOW was the first of many Apple launches on Monday, in what is expected to culminate with the formal launch of the Apple Watch. Our sister publication, MacWorld, is hosting a live blog of the announcements; follow along as the event unfolds.

Why this matters: The world has been waiting for a standalone HBO service for years, especially as cord cutters look to free themselves from pay-TV services such as Comcast, Dish Network, and DirecTV.