A new survey has revealed that a majority of FTSE 100 companies have not yet adapted their websites in any way for smartphone use – potentially deterring the growing number of consumers who now use such mobile devices to connect to the internet.

The survey – commissioned by the Financial Times – revealed that the websites of 69 of the FTSE 100 companies – including International Airlines Group and Rolls-Royce – are currently more awkward and far less user-friendly for mobile users than they are for those accessing the sites via a more traditional desktop route.

Among the difficulties said to be encountered by smartphone users when visiting the non-optimised sites are text which is too small to read, problems in navigating around the site and delays in downloading content.

The survey found that although 22 FSTE 100 companies had made some progress in adapting their sites for smartphone access, only eight of these were ranked as performing ‘moderately well’ – and only one, Marks and Spencer, had managed to achieve a respectfully high user rating.

The survey’s findings are said to be particularly concerning given that smartphones are now used to surf the internet by half of all UK citizens, coupled with predictions by leading search engine Google that over 50 per cent of all internet searches in three years’ time will be undertaken via a mobile device.

In addition to the potential loss of sales through failure to accommodate the needs of mobile users, those conducting the survey also point to the reduced effectiveness of expenditure on web-based marketing and advertising designed to incentivise users to visit company websites.