Apple focuses on proprietary hardware and software integration to drive sales of its products. Google believes future revenue will come from in-app advertising and provides an open Android platform. Microsoft aims to dominate the mobile operating system market with Windows and integrate both hardware and software. Mobile computing is important for driving future internet access and revenues. Success will depend on platform offerings, app stores, and whether standards are open or closed. Google's business model of free Android platform and app store revenues from advertising may allow it to prevail over Apple and Microsoft in this competition.