Apple continues to roll out its iPhone to regional carriers in the United States with the addition of Cricket Communications, a Leap Wireless company. What’s interesting about this particular announcement is that Cricket is a pre-paid carrier so basically they’ve just become the nation’s first wireless operator to offer the unlocked device with a pre-paid plan…

According to a press release, come June 22 you can get an iPhone 4S or iPhone 4 without committing to a long-contract. Instead, you’ll be opting for Cricket’s $55 a month offering that includes unlimited  voice, text and data for smartphones. Of course there is fine print: data throttling starts once you go past 2.3GB.

The luxury of not having to pay service fees for the next two years will cost you in hardware: the iPhone 4S is priced at $499.99 for the 16GB model and iPhone 4 will be available for $399.99. Note that this is a cool $150 cheaper compared to Apple’s asking prices for unlocked iPhones.

Once you get a Cricket iPhone, you can take it on other networks as it’s not locked, which could be of interest to jailbreakers.

Being pre-paid means you can cancel your service at any time, no questions asked (that’s why they sell you the hardware unsubsidized). If you won’t be using the service for a certain period – for example, while traveling abroad – you can temporarily stop paying for your monthly plan and continue whenever it suits you.

Both the iPhone 4S and iPhone 4 will be available in Cricket company-owned stores and select dealers in nearly 60 markets. You can register your interest online.

To my knowledge, this is the first time Apple partnered with a pre-paid carrier to offer the iPhone – and at lower prices than its own stores.

With the Cricket deal and the Pioner Wireless announcement earlier this month, the iPhone has now become available across fourteen carriers in the United States.

Moreover, if Apple dropped the iPhone on a relatively small pre-paid carrier, perhaps the device will soon become available via Boost Mobile and Virgin Mobile, both Sprint properties.

I wonder how such an aggressive roll out across U.S. carriers affects iPhone sales going forward.