Smart phones, smart savings.

The article looks at smartphones, evaluating several retailers and offering suggestions for ways that consumers can save money. Topics include reducing one's cell phone data usage, how to sell, trade, or recycle an old cell phone, and the relative merits of the Android OS, Apple iOS, and Windows Phone mobile operating systems. Money-saving suggestions include haggling over the price of the phone, considering a prepaid phone plan, and avoiding insurance or an extended warranty. Costco, Wal-Mart, and Best Buy are evaluated as cell phone retailers. INSETS: Data-hogging phone habits;When to get a new smart phone;Android phone, iPhone, or Windows Phone? How they compare;Protect the data on your phone