The Asus Eee Pad Transformer TF201 or Asus Eee Pad Transformer Prime is a 2-in-1 detachable tablet from the Asus Transformer Pad series. It is the world's first Android tablet computer with a quad-core processor, and a successor to the dual-core Asus Eee Pad Transformer. It runs Android 4.1. The Transformer Prime was announced by Asus on 9 November 2011. It was released in Taiwan on 1 December 2011, and in Canada and the United States during the week of 19 December 2011.