From the 10K, "the Company owns several patents related to its fleet management solutions and has secured patents pending. These proprietary properties, in aggregate, constitute a valuable asset, although the Company also believes that its business is not dependent upon any single proprietary property or any particular group of proprietary properties."
Their website http://xrscorp.com/ explains a great deal more, but their critical advantage in the EOBR biz (though I'm sure there are others playing catch up) is the idea of using a smartphone to power the EOBR functions. Most EOBR companies require expensive proprietary hardware upfront. XRS uses much simpler hardware because all it does is record required EOBR data that a smartphone can't capture. This lower cost and simpler development environment makes XRS a low cost provider. And as with any low margin business, truckers like low cost.