Supermarket Tesco today announced the launch of its shopping software for PDAs, allowing customers to order their groceries during those long journeys to and from work.

The software, which is compatible with any PDA that links up to a Windows PC, will be available free from Tesco's website from 1 August. It enables shoppers to view over 20,000 products and create their list off-line.

"At last there's something more useful for crushed commuters to do than cursing the rail companies or struggling over cryptic clues," said Carolyn Bradley, chief operating officer at Tesco.com.

Customers simply choose their shopping from the list provided, updates to which will be available to download from the site, and enter their credit card details. This information is then sent through to the store as soon as the user connects to the internet, either via their PDA or when they sync it with their PC.

Tesco claims this is the first PDA shopping software in the world, written in conjunction with DAT Group, it has already gained support from some of the world's leading software vendors.

"This is the killer application that the pocket PC was made for," said Neil Holloway, managing director of Microsoft UK. "Tesco.com has started the next revolution in online shopping."

As yet, no other supermarkets have announced any similar systems but, if Tesco's trials are successful, it won't be long before they follow its lead.