Microsoft’s departing software chief has urged the company to move on from its base of Windows and Office and look to global web devices.

Ray Ozzie made his mark with his ‘Internet Services Disruption’ memo which is seen by many as Microsoft’s manifesto for internet based cloud computing.

Ozzie has made the call for simplicity within Microsoft’s applications as many new smartphones are released in November.

Ozzie said: "Let's mark this 5-year milestone by once again fearlessly embracing that which is technologically inevitable.”

"The next five years will bring about yet another inflection point -- a transformation that will once again yield unprecedented opportunities for our company and our industry catalyzed by the huge and inevitable shift in apps and infrastructure that's truly now just begun."