RIM founder Mike Lazaridis and long serving chief executive Jim Balsillie, the duo behind the international success of a phone once so popular it was dubbed the 'crackberry', lost control of the company at the end of last year. Shareholders demanded a shake-up after repeated profit warnings, months of delay to the launch of the BB10 software, and a botched entry into the tablet market with the poorly selling BlackBerry PlayBook. Lazaridis and Balsillie resigned their shared co-chair and chief executive roles at the end of 2011, with internal candidate Thorsten Heins becoming chief executive, and Balsillie left the board at the end of March. Financial decline has been swift, with RIM reporting a pre-tax loss of $137m in the quarter ended 3 March 2012, compared to a $1.2bn profit just a year before. The company has 77m BlackBerry subscribers around the world, but sales tumbled 25% last quarter, with US revenue plummeting more than 50%. This article was amended on 3 May 2012.