Until now, users of Reddit worldwide had to use third-party apps from the App Store to use the site from a mobile device. These apps were, of course, unofficial.
Many of these projects were created by fans, who couldn't wait for the official app. We knew the official app will be coming soon, it was being developed since 2014.
Beta testing took a place in December 2015 and today we can see the official release of the Reddit official app (for Android).