Asda has today launched a transactional iPhone app that allows users to purchase groceries from the supermarket, and run price comparisons against its competitors.

This comes more than a year since the launch of Tesco’s m-commerce iPhone app, reviewed on Econsultancy in September 2010.

The app also integrates Asda’s existing ‘Price Guarantee’ app, which allows users to check the cost of their shopping basket against the likes of Tesco and Morrisons.

Asda press officer Jo Newbould said that the company focused on what it can give customers that’s different to existing supermarket apps. 

We wanted to get it right, and believe that the integration of our Price Guarantee app is something people will find truly useful.”

According to Asda, 60% of customers who access the mobile site, which went live in August, do so using an iPhone. It has therefore focused on its key demographic, and the Android app is not scheduled for release until early 2012.

The old Price Guarantee app achieved more than 300,000 downloads and Asda says it expects to see a high demand for its new offering.

Of the other big grocery retailers only Tesco offers a transactional mobile app, so while Asda isn’t exactly pioneering new territory, it is obviously making efforts to keep up with its neighbours.