Apple made its emoji keyboard widely available worldwide in 2011.
The global rollout came with iOS 5, after Apple had previously offered emoji support in Japan. Before the worldwide release, users in some regions relied on workarounds or third-party applications to enter emoji.
Apple’s international rollout helped move emoji from a mainly Japanese mobile-phone feature into everyday global digital communication. The keyboard made the symbols easy to insert in messages, email, and social media, accelerating their adoption on smartphones.
This date is sometimes confused with the iPhone’s 2007 launch or Apple’s Japanese emoji support, which arrived earlier. The question concerns broad worldwide availability of the built-in emoji keyboard, not the first appearance of emoji on an Apple device.