Auto Trader mobile has announced that it achieved 2.2m unique users in the month of January 2012.
The brand says that this represents 150% growth in car searches made via mobile in the past year.
eBay, which expects to see $5bn of sales come via mobile for 2012, also recently identified Motors as one of its core sales categories.
It upgraded its Motors app to allow people to search for a vehicle simply by taking a picture of it, since eBay currently sells around 2,800 vehicles worldwide each week through its mobile platform.
eBay's Clare Moore-Bridger said the popularity of buying and selling cars through mobile had been surprising.
People don't expect our customers to be willing to buy cars using their phones, but we have sold Bentleys and Porsches through mobile in the UK.”
Auto Trader is now fighting to retain its place in this space, and has revealed a multitude of behavioural data on how people use it to search for cars.
Years of credibility in the car trade means that it's a natural choice for many, with its focused offering appealling to those that want to buy from a specialist.
The stats have been compiled into the infographic below, taken from the Auto Trader's mobile site, iPhone app and android app.