Apple announced that Tim Cook will step down as CEO and will be replaced by John Ternes, senior vice president of hardware engineering, the company said in a news release on April 20. Cook will remain CEO until September 1, when Ternes will take over. Read Next: 9 Tips So You Don’t Have to Be Un-Retired to Survive Cook became CEO of the tech giant in 2011. He will become the executive chairman of the company…