The availability of mobile banking applications is helping drive the strong growth in online shopping, a survey shows.New research by PwC and Frost and Sullivan puts online retail sales at 6.3 percent of total Australian retail sales in 2011.The researchers said they expect online shopping expenditure to grow 17.6 per cent, from $13.6 billion in 2011 to $16 billion this year. They expect a compound annual growth rate of 14.1 per cent out to 2016.This year, 9.6 million Australians over the age of 15 will make an online purchase. Eighty-eight per cent of online shoppers expect to increase their online spending in the coming year.Lower prices were cited as the main reason for the increase in online shopping, followed by greater convenience and greater choice.Factors contributing to this growth are the entry of more online retailers, an increasing number of manufacturers using the internet to go direct to consumers and an expansion in online services.Another factor is the strong growth in the number of consumers using mobile devices to browse, shop and transact.Fifty-seven per cent of online shoppers said they had increased their spending on mobile devices over the past 12 months.