Mike Lazaridis and Jim Balsillie, the co-CEOs of Research In Motion, have resigned following months of investor pressure for a change at the helm of the struggling BlackBerry maker.

COO Thorsten Heins was named president and CEO of the Waterloo, Ontario-based RIM, which has been steadily losing market share to Apple's iPhone and handsets powered by Google's Android software.

Heins, 54, joined RIM from German industrial giant Siemens in December 2007 and served as senior vice president for hardware engineering before becoming COO for product and sales in August 2011.