Earlier this year, FreedomPop said it was working on an iPhone case with an integrated cellular radio that would provide users with free mobile broadband access on Clearwire's 4G WiMAX network. Now, the company is taking pre-orders for this 4G WiMAX sleeve.

Each sleeve will cost US$99 and will include 500 MB of free mobile data. This is a drop from the planned 1 GB of data FreedomPop hoped to offer. You can bump up that data by participating in a social service that'll earn you an unspecified amount of data for connecting with your friends. Customers can also transfer unused data to other customers who need the extra capacity. (Note that the company's pre-order page still says "up to 1 GB of free data.")

You can read more about the FreedomPop case on the company's website and watch a promotional video about the sleeve in the YouTube video below.