Microsoft recently unveiled plans to launch its Cortana digital voice assistant on arch-rival Google's Android OS, but until now, you could only use it as a standalone app. However, the latest beta ( lets you activate Cortana instead of Google Now by pressing and holding your Android home button. That's a new way for Android users to test the app's friendly ways and be tempted away from the businesslike Google Now. Since Cortana relies on Bing, it's also a sneaky way for Microsoft to do an end-run around Google search.