Specifically designed for mobile phones and mobile devices, m.marksandspencer.com allows customers to shop Marks' website and browse more than 24,000 products on the move.
M&S is the first high street retailer to launch such a site and has ensured that the new m.marksandspencer.com works in sync with its existing transactional website so that customers can log in to and manage their regular web-account from their mobile phone.
Negating the need to download an app or any software, shoppers simply type www.marksandspencer.com into their phone's internet browser. Once there, they can browse more than 24,000 M&S products, including clothing, home and furniture and technology.
Director of M&S Direct David Hughes said: "This is a major step forward in mobile retailing. Mobile optimised shopping sites have been done before by specialist retailers, but M&S entering the market with 21 million customers, one of the UK's most recognised brands and a well-known range of products, changes the mobile retail landscape."
He added: "Even before the site has launched, hundreds of thousands of customers are already shopping with us on their mobile phones and market data is telling us that this will soon be millions. The new site allows these customers to browse and buy from their mobile device without the frustrations that come with trying to do the same on a transactional website."
In June 2008 M&S launched SMS and mobile marketing and is now sending around a million text messages a month to listed customers. Its current website, marksandspencer.com, which was launched in 2000, is one of the UK's top 10 retail websites, with more than 4 million customers.
According to mobile marketing agency Incentivated, one in ten of all internet pages in the UK are viewed on a mobile device, while Yahoo expects the number of adults using mobile internet to double in the next two years, with 50% of the UK adult population using mobile web by 2012.