Sydney Morning Journal – Emily, a 30-year-old economist, became so addicted to Candy Crush Saga, a free iPhone game, that she would lie awake at 1am imagining her finger swiping across the screen to line up rows of brightly coloured lollies. Three in a row would deliver a satisfying squelch as they burst and moved the ­Melbourne mother-of-two closer to the next level. Candy Crush Saga is a simple game but the hold it has over its devoted followers is complex and incredibly strong. They are reminiscent of gamblers who can’t help but feed another $20 into a poker machine...