AT&T has officially confirmed that starting on September 6, any customer using a smartphone will need to subscribe to a data plan. AT&T said in a statement, "Smartphone users tend to consume a higher amount of data services, like advanced e-mail, mobile Web, applications and more. Being able to take full advantage of these features without having to worry about a fluctuating or unusually high bill generally leads to greater customer satisfaction, so effective Sept. 6, smartphone customers will need to subscribe to a data plan, as the vast majority of customers already do." This change will apply to new lines and any renewed contracts after September 6. Existing customers who already have smartphones without data plans will be able to stay with their current plan. The data plan costs $30 per month and applies to iPhone, BlackBerries, Windows Mobile, Symbian and Palm devices.