AT&T to introduce shared-data plans (AP) NEW YORK - Following in Verizon's footsteps, AT&T Inc. said Wednesday that it will introduce wireless plans that let subscribers connect up to 10 phones or other devices. Connected phones get unlimited calling and texting, and all devices get wireless data access. The devices tap into a limited pool of data usage, which gets renewed each month. Verizon introduced its "share everything" plans on June 28, replacing nearly all of its traditional phone plans. AT&T says its "mobile share" plans will debut in late August, but it is keeping its current individual and family plans. AT&T's prices will track closely with those of Verizon. One smartphone with 1 gigabyte of data will cost $85 per month with AT&T, compared with $90 with Verizon. Two smartphones and a tablet computer with 6 gigabytes of shared data will cost $170 on either carrier. AT&T is the country's second-largest cellphone company, behind Verizon. AT&T, which is based in Dallas, has 76.8 million direct wireless customers, and millions more through wholesale arrangements. AT&T's and Verizon's shared-data plans are intended to stimulate the adoption of non-phone devices such as tablet computers and USB modems for laptops by making monthly service cheaper. Analysts believe Verizon's plan will reduce its service revenue in the short term but pay off in the long term as families add more devices. AT&T said earlier this year, before Verizon announced its plans, that it was looking at introducing shared data plans soon. It hadn't offered details then. Under the mobile-share plans, AT&T subscribers will pay a monthly fee for one smartphone and choose a bucket of data usage on top of that. Total costs will range from $85 for 1 gigabyte per month to $230 for 20 gigabytes. After that, subscribers can add other devices to share that bucket of data, paying an extra monthly fee for each one. A basic, non-smartphone will cost $30 per month and a tablet, such as an iPad, will cost $10. Additional smartphones cost $30 to $45 each, depending on the size of the data plan. AT&T faces a problem in that subscribers can move SIM cards, or subscriber identity modules, between devices. The SIM card identifies the devices to the network, and in the case of phones, contains the phone number. Subscribers will be tempted to move a SIM card from a basic phone, for which they pay $30 per month, to a smartphone, which can cost as much as $45 per month. AT&T's chief marketing officer, David Christopher, said the company can tell which type of device a card resides in, but didn't specify how the company would handle wandering SIM cards. "If a customer moves SIMs, we'll have to look at those situations and act appropriately if that happens," Christopher said. SIM cards are rare in Verizon devices.