The app is aimed at people who are busy and don't always have time to look for the breaking news, weather alerts and information they want and need.
"Notifications are becoming one of the primary ways people first learn about things wherever they are," wrote Julian Gutman, a Facebook product manager in a blog post. "Everyone has different interests, so whether you're into sports, celebrities, news, movies, music or shopping, Notify makes it easy to find notifications you're into with a broad selection of great 'stations' across a variety of categories."
For the new app, Facebook teamed up with news outlets and organizations including Fox Sports, The Weather Channel, CNN and Vogue.
Once a user downloads the app, he or she can set up a personal mix of notifications. Then when one of those organizations has an update, it's pushed to the user, popping up an alert on the user's lock screen.
"Notifications are important, and it makes sense for someone, in this case Facebook, to try to centralize them and give users a way to manage them," said Ezra Gottheil, an analyst with Technology Business Research.
He added that Notify should help Facebook in two ways.
"First, this is an important category of app, and Facebook is an early entrant, so with this, Facebook keeps people using Facebook apps," he said. "Second, some of the notifications are based on the main Facebook app, and probably on other Facebook apps, so they bring the eyeballs back to other Facebook apps, as well."
Traditionally, Facebook users have followed their favorite news outlets, receiving information from them on their News Feeds. When a user clicked on one of those links, they were taken to the story on the news outlet's own site.
With Notify, the link will open up inside the app itself. App users also will be able to share the news with friends via email, text or a social network - obviously, including Facebook.
The Notify app is available for U.S. iPhone users today from the App Store.
Facebook's new news alert app is an answer to similar efforts from social media rivals. Twitter recently launched Moments, a news aggregation service for its mobile users, while in January Snapchat unveiled a feature called Discover.
Its arrival on the iPhone alone could also be a shot across Apple's bow; the iOS maker recently launched its own News app.