This IDC Retail Insights report notes that some 48 million shoppers will use their smartphones in stores as they shop for the winter holidays this year. They'll check prices, read product reviews, and look at other products. These "showrooming" practices will influence at least $0.7 billion in retail holiday sales, perhaps as much as $1.7 billion — some 0.1–0.3% of the $586.1 billion in holiday sales projected by the National Retail Federation. "Showrooming will hit several categories of merchandise," said Greg Girard, program director, Merchandising Strategies. "Its impact will be felt beyond consumer electronics — the category most exposed to showrooming risk — into apparel and footwear, books and electronic media, children's toys and games, appliances, and sporting goods. Our research found bright spots. From the vantage point of technology, engaging the showrooming customer in an omnichannel web of digital and physical experience is the key. Five technologies stand out as critical: mobile-optimized Web sites, smartphone apps, online digital content inside stores, technologies that make stores and Web sites equally convenient to shop, and competitive price information via QR codes."