Steve Jobs, billionaire co-founder of Apple and the mastermind behind an empire of products that revolutionised computing, telephony and the music industry, has died in California at the age of 56. Jobs stepped down in August as chief executive of the company he helped set up in 1976, citing illness. He had been battling an unusual form of pancreatic cancer, and had received a liver transplant in 2009. Jobs wrote in his letter of resignation: “I have always said if there ever came a day when I could no longer meet my duties and expectations as Apple’s CEO, I would be the first to let you know. Unfortunately, that day has come.” Apple released a statement paying tribute: “Steve’s brilliance, passion and energy were the source of countless innovations that enrich and improve all of our lives … The world is immeasurably better…