Apple unveiled new software for its computers, smartphones and tablets Monday as it sought to halt the encroachment of rivals like Google and Samsung on its premium products, dpa reported. Apple CEO Tim Cook unveiled the new operating systems in the opening address of Apple\'s annual WorldWide Developer Conference in San Francisco. The company, which has seen its stock fall from a high of more than 700 dollars last September to under 450 dollars currently, badly needs a new hit to reassure investors and customers that it is still capable of maintaining its lead. But with any major new hardware release of new iPhones and iPadsstill months away, the focus was on new Macbook Air laptops and new operating systems for both personal computers and mobile devices. Cook insisted that despite the advances of rivals, Apple\'s mobile operating system iOS remained the number one in the market, boasting of 97 per cent satisfaction and more than twice as much web use as Android. The gap would grow with the introduction of iOS 7, said Cook, who called it \"the biggest change to iOS since the introduction of the iPhone.\" As expected, the new software features strikingly different visual cues with a flat, translucent and colourful design replacing a 3D opaque pallet that featured lots of greys and blues.