Google is rolling out a new service that lets users buy retail items directly from the search results page on mobile devices in an effort to make mobile search more useful and give advertisers a new way to attract customers.

A new link reading “Buy on Google” will appear in the adverts that show up after users search for certain retail items. Clicking on that link will take the user to a retailer-branded product page hosted by Google where they can can get more information about the product, like reviews, and select item quantities. A checkout button will let them enter and save payment information and provide a shipping address before placing the order.

On Wednesday the company provided more information about how the service, Purchases on Google, will work.

It says it is still testing the feature, with a limited number of retailers participating such as athletic-clothing maker Under Armour, handbag and luggage retailer eBags, and office-supply vendor Staples.

Google will include a buy button in its search results on mobile devices in the coming weeks, a move that could give online shoppers an easier way to buy products on small screens.

The change might also give consumers an alternative to mobile apps from companies like Amazon and eBay, although it might jeopardise retailers’ ability to directly market to their customers.

The products will still be provided and sold by the retailer and not by Google. Macy’s is in talks with Google to take part in the launch of the button.

The buttons will accompany only sponsored search results, not regular results driven by Google’s basic search algorithm. At first they will only appear with a small percentage of Google’s search traffic.

Over time, the buttons could help Google expand its search service beyond information and links to also encompass an online storefront.

To help preserve retailers’ connection with their customers, Google will allow consumers to opt in to the same marketing programs they would be exposed to had they bought the item on retailers’ own sites.

Other sites such as Facebook and Twitter are also trying out new ways to enable users to make purchases without leaving their sites.

The date when Google will launch its buy button has not as yet been ascertained.