With the unofficial start of the holiday shopping season just a few days away, Reuters takes a look here at how retailers are connecting with shoppers on their smartphones. Lowe’s, for instance, is issuing tends of thousands of iPhones to staffers to help give users product information and reviews, while J.C. Penney recently overhauled its mobile web site to make it easier for users to share wish lists, among other things. While mobile is still just a fraction of overall e-commerce sales, the 300 largest U.S. mobile merchants are expected to generate $5.37 billion in sales this year, more than doubling last year’s sum. So if you’re a retailer, your mobile site and apps should be ready to go this week.