The Friends Photo Tool is a new photo-sharing product from Facebook that lets anyone customize their photos with text or emoji and share them with their friends.

The tool launched in the United Kingdom and spread virally around the world. People from 124 countries used the tool to share what makes their friendships unique and the best images were then dynamically fed to more than 1,000 digital billboards across the UK. As people shared more photos, the screens were refreshed with new content showing a real-time pulse of friendship.

The Friends Photo Tool gave everyone a fun way to share their friendships and, with the help of digital OOH, celebrate them with the world.