Flickr ( ; ) is an American image hosting and video hosting service, as well as an online community, founded in Canada and headquartered in the United States. It was created by Ludicorp in 2004 and was a popular way for amateur and professional photographers to host high-resolution photos. It has changed ownership several times and has been owned by SmugMug since April 20, 2018. Flickr had a total of 112 million registered members and more than 3.5 million new images uploaded daily. On August 5, 2011, the site reported that it was hosting more than 6 billion images. Photos and videos can be accessed from Flickr without the need to register an account, but an account must be made to upload content to the site. Registering an account also allows users to create a profile page containing photos and videos that the user has uploaded and also grants the ability to add another Flickr user as a contact. For mobile users, Flickr has official mobile apps for iOS, Android, and an optimized mobile site. History Flickr was launched on February 10, 2004 by Ludicorp, a Vancouver-based company founded by Stewart Butterfield and Caterina Fake. The service emerged from tools originally created for Ludicorp's Game Neverending, a web-based massively multiplayer online game. Flickr proved a more feasible project, and ultimately Game Neverending was shelved, Butterfield later launched a similar online game, Glitch, which was shut down on November 14, 2012. Early versions of Flickr focused on a chat room called FlickrLive, with real-time photo exchange capabilities. The successive evolutions focused more on the uploading and filing back-end for individual users and the chat room was buried in the site map. It was eventually dropped as Flickr's back-end systems evolved away from Game Neverendings codebase. Key features of Flickr not initially present are tags, marking photos as favorites, group photo pools and interestingness, for which a patent was granted. In addition to being a popular website for users to share and embed personal photographs and an online community, in 2004, the service was widely used by photo researchers and by bloggers to host images that they embed in blogs and social media. Yahoo! acquired Ludicorp and Flickr on March 20, 2005. The acquisition reportedly cost $22 million to $25 million. During the week of June 26, 2005 to July 2, 2005, all content was migrated from servers in Canada to servers