Microsoft seeking to regain its footing in the fiercely competitive mobile market is expected to unveil a new smartphone platform at the industry’s biggest trade show. The US software giant has remained tight-lipped about what CEO Steve Ballmer will announce at the Mobile World Congress in Barcelona, Spain, but analysts widely believe he will reveal an upgrade of the Windows operating system.

Microsoft has been up against strong competition from telecommunications giant Nokia’s Symbian platform and internet giant Google’s Android. “They do seem to have been pushed on to the backfoot with the Android which seems to have caught them on hoof,” said Jeremy Green, mobile analyst at research firm Ovum.