League of Explorers ticket dates

March 22, 2013 is the date Hearthstone was announced at Penny Arcade Expo.

March 11, 2014 was the official release date for Hearthstone for Windows and OS X.

On December 15, 2014, Hearthstone was released for Android tablets.

April 14, 2015 was the release date for the smartphone versions (both iOS and Android) of Hearthstone.

Each date was a significant announcement/release milestone for Hearthstone.

Temple of Orsis - March 22 2013, was the date of the original announcement of Hearthstone.

Uldaman - March 11 2014, was the release date for Hearthstone.

The Ruined City - December 15 2014, is the date of Hearthstones Android tablet release.

Hall of Explorers - April 14 2015, is the date of Hearthstone's release for mobile devices (iPhone and Android).