Amazon's upcoming smartphone will be exclusive to AT&T, according to The Wall Street Journal. The e-commerce giant is widely expected to introduce its first ever smartphone at a media event on Wednesday, building on its Kindle Fire line of Android tablets. Amazon already has a relationship with AT&T; the carrier provides wireless service to its tablets and e-readers, but securing an exclusive deal with Amazon for its smartphone would be a major extension of that partnership. It's unclear whether Amazon will also offer the smartphone through its online store SIM-free or if it will truly be limited to AT&T customers, but regardless, the majority of potential buyers are unlikely to buy a phone without a contract. Although the major players in the smartphone industry now offer their phones across all of the larger carriers in the US, it's not uncommon for exclusive deals to be signed for new entrants to the market.