It announced the move at the start of its F8 developers conference, which is being held in San Francisco.
The decision to launch the Audience Network has the potential to disrupt the ad sector thanks to the depth of knowledge the firm has about its users.
But one company watcher said the social network would need to be wary of privacy concerns.
"Facebook will have to make sure from the outset that it sets some stringent guidelines as to exactly the type of data that it shares with advertisers," Lara O'Reilly, senior reporter at MarketingWeek magazine, told the BBC.
The platform could become a huge money spinner. An industry study suggested more than £1bn was spent on mobile ads in the UK alone in 2013, a rise of 93% on the previous year.
Facebook suggested it would deliver better click-through rates than its rivals because it had a better chance of delivering "relevant and interesting" material to the public.
"The mobile ecosystem needs a way to deliver these kind of native, personalised ads to people, and I'm glad that we can deliver more than one million active advertisers to your apps," said Facebook's chief executive Mark Zuckerberg at the conference.Facebook v Twitter
The social network is entering a competitive space. In addition to Google's AdMob and Apple's iAds platforms, several smaller firms are also competing to provide the adverts shown on mobile phones and tablets.Flappy Bird was reported to have earned $50,000 a day through ads
Millennial Media, Flurry and Nexage are all promoting their own versions of "programmatic buying" - a way for firms to target their ads at a specific type of consumer via a chosen type of app at an appropriate time and geographic location.
Twitter - another social network - has already moved into the area following its acquisition of the MoPub mobile advertising network last year.
It recently started letting clients buy ads on both the Twitter feed and MoPub using the same software, as it starts to integrate the products.
But Ms O'Reilly thinks Facebook will ultimately gain the edge because it has access to more information.
"The problem for Twitter is the amount of verifiable data it has on users - their interests and likes," she said.
"Their tweets can sometimes be false and obviously people don't have to give information about how old they are, the types of movies they like and so on.
Other announcements made at F8 included news that Facebook is changing the way data is shared with other developers.
In the past the network's members had been able to authorise third-party apps to obtain information about their Facebook friends.
That is now changing so that each user instead has to give permission to an app before it can see any data about them.Facebook is introducing a new anonymous login function to address privacy concerns
In addition, the firm is also introducing a new function called Anonymous Login.
This will allow users to access a third-party service via their Facebook ID, but do so without releasing any details about them.
The aim is to allow people to try out apps that rely on them having a Facebook login without the user having to reveal who they are until they feel that they can trust the new software.
Mr Zuckerberg described it as a way to test "apps without fear".Like buttons are coming to mobile apps
Facebook also revealed it would be making a tool available to developers to add its "like" button to their apps, allowing users to highlight and share content they had seen via the social network.
This should both drive more traffic to the third-party apps and provide Facebook with more data to target its ads.