Our CEO, @dickc, will step down as CEO, and we’ll welcome @jack as Interim CEO on July 1 #TWTRannouncement: http://t.co/q8Ygg91jzc
— Twitter (@twitter) June 11, 2015
Jack Dorsey was the original CEO of Twitter until 2008 when fellow co-founder Evan Williams took over. In 2010 Costolo took over as CEO. In the last five years under Costolo the service has had many design changes and controversial changes. The biggest thing to affect Android users is the change to the Twitter API which has killed many awesome 3rd-party apps. Twitter is everywhere and it should continue to grow under Dorsey.