30% of US consumers who purchased Apple iPhone 3G in the summer of 2008 switched from other mobile carriers to join AT&T, the exclusive mobile carrier for the iPhone in the US. 23% of consumers, on average, switched carriers between June and August 2008. 47% of new AT&T iPhone customers that switched carriers switched from Verizon Wireless, another 24% switched from T-Mobile, and 19% switched from Sprint. Before the launch of the iPhone 3G, iPhone sales represented 11% of the consumer market for smartphones (January through May 2008); however, after the launch of iPhone 3G, Apple commanded 17% of the smartphone market (January through August 2008).