By Sam Mattera

When it comes to the U.S. smartphone market, it’s mostly a two-horse race. Cumulatively, Apple (NASDAQ: AAPL ) and Samsung (NASDAQOTH: SSNLF ) sell two out of every three smartphones, with smaller manufacturers such as HTC and Motorola fighting for what’s left.

But that could change next year, when Asus brings its PadFone to the United States. The device, powered by Google’s (NASDAQ: GOOG ) Android, is particularly revolutionary and has the potential to disrupt the mobile market.

Asus’ PadFone combines a tablet with a smartphone
The term “phablet” has arisen to define phones such as Samsung’s Galaxy Note III — too small to be a tablet, yet too large to be a smartphone: a hybrid of form factors. But Asus’ PadFone might be the ultimate phablet: Buyers get both a tablet and smartphone, but none of the trade-offs that traditional phablets entail.

Normally, the PadFone Infinity is a standard, 5-inch smartphone running Google’s Android. It has a high-end processor and 13-megapixel camera. In other words, it’s largely indistinguishable from many other Android smartphones. But it has one huge advantage over its competitors — a proprietary dock.