as we build a great network, we're also building upon our history of industry-leading innovation to put together the best lineup of wireless devices we've ever offered. Our launch with Apple of their iPhone is a classic success story of an alliance between two of the world's leading technology firms. The iPhone's success also raised the profile for our expanding array of smartphones, which customers can use to send e-mail, access the Internet, get directions, take pictures, download video and music and play games.
for both business customers and consumers, we're focused on improving the customer experience. We've made it easier than ever for customers to do business with us. Our 2,200 AT&T retail locations, our always-open online store (att.com) and our relationships with retailers such as Wal-Mart, Best Buy and RadioShack give us an unmatched ability to place our products into customers' hands.
And that lineup now includes a growing number of AT&T ExperienceSM stores. They bring the concept of mobility to life, giving people the chance to learn firsthand how our products — wired and wireless — work together to connect customers to their world.
As the largest provider of prepaid mobile phones, we're also expanding access to mobility to consumers who might not want — or can't afford — an ongoing service plan.
In 2007, through strong internal growth combined with strategic acquisitions, we expanded our subscriber base by more than 9 million. And, as we've enhanced network performance and introduced more data-capable devices, the revenues have followed. Our service revenues were up nearly 15 percent in 2007, and our annual data revenue growth exceeded 63 percent.