Apple is the world’s top-ranking smartphone manufacturer when it comes to customer satisfaction, according to the results of J.D. Power’s 2009 Wireless Consumer Smartphone Customer Satisfaction Study. Apple ranked highest among smartphone manufacturers with a score of 791 out of 1000, performing strongly in the categories of ease of operation, operating system, features and physical design. By comparison, it struggled only but very substantially in the battery category, where it rated below average. LG and Samsung follow Apple in the rankings, with scores of 772 and 759, respectively. Interestingly, the study also found that 40 percent of smartphone users report dropping their landlines in favor of their mobile, compared with just 28 percent of traditional handset owners who had done the same. Overall, smartphone users reported sending and receiving an average of 17 emails per day on their devices, and 82 percent said they regularly use their device’s personal information management capabilities — such as address books and to-do lists — to stay better organized.