Beginning Oct. 25, new AT&T Inc customers will only be able to buy Mobile Share plans, which involve higher data fees, AT&T said on Friday. The company said that it tries to offer its customers simplified options that allow them to share data across multiple devices. With the change, AT&T's new customers will have the choice of any of the company's Mobile Share plans, which start at $50 a month for a basic phone or $70 a month for a smartphone - both of which include unlimited talk and text and 300MB of data that can be shared.

For current AT&T's customers, there is no change. They can choose to switch to Mobile Share, or they can continue to use, upgrade or downgrade their existing plan.

Generally, customers subscribing to shared-data plans might be less inclined to switch to another carrier if their cellular service for several devices, including smartphones and tablet computers, is attached a single plan.

Carriers also see the plans as a way to encourage subscribers to add more devices and increase how much they spend on cellphone service.

Competition is ramping up in the U.S. wireless industry. AT&T is facing aggressive competition from No. 4 U.S. operator T-Mobile US Inc.