The iPhone 4S is available on AT&T, Verizon Wireless and Sprint networks, but another carrier will reportedly sell Apple's new smartphone. On Wednesday, regional carrier C Spire, formerly known as Cellular South, released pre-order details for the iPhone 4S on its website.

Pre-orders are not available just yet, but users can provide their e-mail addresses and phone numbers to receive future notifications when the iPhone 4S becomes available.

C Spire offers an extremely fast network with extensive coverage, as well as flexible 'CHOICE PLANS' that offer its users infinite data, text and picture messaging. Despite the wide coverage area, comparable to that of T-Mobile, C Spire store locations are almost exclusively found in the state of Mississippi, with a few stores located in southern Alabama and Tennessee.

C Spire customers receive exclusive apps like Scout, which helps its user discover personalized and relevant applications, and a rewards program called Percs, which gifts customers for contributing their ideas to improve C Spire's wireless services.

Apple has not yet explained why it chose C Spire as a carrier over more a more well-known carrier like T-Mobile, but C Spire apparently has greater voice and data coverage than T-Mobile.

Unfortunately for T-Mobile, the choice is not up to them. According to Cole Brodman, T-Mobile USA's executive vice president and CMO, the ball is in Apple's court.

We'd love to have the iPhone whenever Apple makes that available, Brodman said. We are waiting for that phone call.

Apple would benefit plenty from a T-Mobile partnership. T-Mobile reports that 75 percent of all devices sold by the company are smartphones, and 90 percent of those phones are Android-powered.

T-Mobile's plans to merge with AT&T are still in limbo, pending the results of an antitrust lawsuit filed by the U.S. Department of Justice to block the deal.

We still expect it to happen, Brodman said. Our customers win either way.

With C Spire, Apple will make the iPhone more accessible to a broader market by building ties with a small, regional carrier.

Apple has already sold 4 million iPhone 4S units, which is almost twice as many as the iPhone 4 in the same period of time.