The App Centre aims to showcase "the best social apps" from across the web and is available on Facebook.com, as well as Facebook's iOS and Android app.
It launched in the US in June and is continuing its global rollout.
Facebook first announced news of its plans for an app store as a way to drive additional revenue streams through payments on the same day, ahead of its $104 billion IPO in May.
The store will also allow developers to charge for Facebook apps for the first time and set up pages to promote their product on Facebook.
Consumers will need to use Facebook Credits to purchase the apps, meaning Facebook will take a 30% cut of revenue.