The Globe and Mail reports in its Tuesday edition that there is a general rule about consumer electronics: The older a device becomes, the more competitors appear and prices fall. A New York Times item inside The Globe says this was true for televisions, personal computers and portable music players. It was supposed to happen with smart phones -- but the iPhone has defied gravity. On Tuesday, Apple will unveil the 17th iteration of its flagship product. Remarkably, at an age in which most consumer devices have lost some of their appeal to users, Apple has increased its share of smart phone sales over less expensive rivals. Over the past five years, the iPhone has increased its percentage of total smart phones sold around the world while expanding its share of sales in four of the world's largest regions: China, Japan, Europe and India. In the United States, the iPhone's largest market, the device now accounts for more than 50 per cent of smart phones sold, up from 41 per cent in 2018. The gains have helped it claim about one-fifth of the world's smart phone sales, up from a low of 13 per cent in 2019. Apple has expanded its smart phone empire as the broader industry has faltered, with Android sales plummeting.