For anyone who has ever tried to carry out safe shopping online from a smartphone or tablet, it may be apparent that doing so can be a bit of a mixed experience.

While using a dedicated app developed by a retailer to allow orders to be placed is likely to result in customer satisfaction, problems arise when using a mobile browser to visit e-commerce sites which, in many cases, are designed predominantly for people using desktop PCs and laptops.

Last month, Google launched a scheme to make it easier to find optimised sites by tagging search results as mobile-friendly if they meet certain usability criteria. And now Microsoft's rival search engine, Bing, has followed suit with its own mobile-friendly tag, according to Econsultancy, which is good news for consumers who are sick of stumbling upon unwieldy sites on their portable devices.

At the core of Bing's new push for mobile-friendliness is a focus on sites which are designed for ease of use when interacting via a touchscreen display. Sites which have eliminated incompatible plug-ins, such as Flash, are also given the seal of approval by the search engine.

While Google has chosen to actively penalise sites which are not optimised for mobile use by ranking them lower down on its results pages, Bing is less punitive on the whole. But a spokesperson explained that it is still keen to make sure that mobile-friendliness is a top priority for sites.

This means retailers will really need to improve their browser-based user experiences and cater to a mobile audience, or else risk being alienated by customers and search engine providers alike.

With more and more people using their handsets to indulge in safe shopping online while they are on the move or sitting on the sofa, it is easy to see why retailers need to realign their priorities.