The Windows Phone 8.1 version was released on the Microsoft Store on December 10, 2014. Minecraft Pocket Edition Lite, which was essentially version 0.2.1 without world save functionality and had limited inventory items, was available until October 21, 2013. On September 13, 2012, the Pocket Edition was made available for purchase on the Amazon Appstore. It was later released for other Android devices on October 7, 2011, and iOS on November 17, 2011. Pocket Edition was initially launched exclusively for the Xperia Play on Google Play for US$6.99 on August 16, 2011. To assist with clarification, the Minecraft community referred to these versions collectively as Bedrock Edition due to Bedrock being the name of the C++ codebase from which they all derive. When these editions received the Better Together Update, the 'Edition' subtitle was removed, and the official name for all of these editions became Minecraft. Pocket Edition introduced the Bedrock Engine, which was later ported to non-mobile platforms as four other editions of Minecraft: Windows 10 Edition, Gear VR Edition, Apple TV Edition, and Fire TV Edition. Minecraft: Pocket Edition (informally known as MCPE or PE) was the former title of the Bedrock Edition of Minecraft developed by Mojang Studios for mobile devices before 1.2.0, although subsequent builds are still commonly (if erroneously) referred to as Pocket Edition.