Google did advertise their Nexus 4 device as an Android smartphone that will feature support for HSPA+ data speeds, but folks who tinkered with their Nexus 4 realized that a 4G LTE chip lies within, and if you happen to reside in the Great White North, you are able to use it to hook up to the Rogers or Telus networks, now how about that for some hardware sleuthing? Majority of the AT&T customers in the US remain on the relatively slower HSPA+ capability, and it seems that select parts of the US has AT&T making use of a wireless band that supported by the Nexus 4. In a nutshell, if you happen to live in one of those bright spots, then you can use the Nexus 4 as a 4G LTE device – right in the US, of course.
Bear in mind that the Nexus 4 is able to hook up to LTE band 4, although not to the majority of the other LTE bands. When in the US, AT&T will use band 17 primarily, but it so happened that they used Band 4 in select markets, hence explaining this phenomenon. Are you one of the lucky ones, or have you decided to uproot yourself and the entire family to Canada instead?