Software giant Microsoft has taken another step along its new, platform-agnostic mobile strategy with the launch of a public beta of its Cortana personal digital assistant app on Android.

Cortana originated as a proprietary feature of Microsoft’s Windows Phone mobile OS, as the company strove to persuade OEMs and consumers to adopt the platform over Android or iOS. Now that Microsoft has effectively given up on acquiring significant global smartphone market share for Windows Phone it is instead looking to exploit its mobile products across all platforms.

Assistance tools such as Google voice search (“ OK Google”) and Google Now already come as standard on Android devices, but they’re a bit piecemeal and don’t offer the one-stop-shop digital assistant package promised by Cortana and Apple’s Siri. One of the crucial features in the Android version of Cortana is the ability to launch it just by long pressing the home key, thus replacing Google voice search, but the “Hey Cortana” command is still unavailable on Android.

The latest version of Microsoft’s desktop OS – Windows 10 – comes with Cortana preinstalled and Microsoft is positioning Cortana on Android as an extension of the PCtool. This is also consistent with Microsoft’s strategy of making better use of its massive PC installed base to improve its fortunes in mobile.

“The Cortana app can do most of the things Cortana does on your PC or on a Windows phone,” said Microsoft’s Susan Hendrich in a blog post. “With the app, you can manage your hectic lifestyle by setting and getting reminders, searching the web on-the-go, tracking important information such as flight details as well as starting and completing tasks across all of your devices.”

It remains to be seen how much demand there is ever likely to be for an alternative digital assistant app on Android, or even if people want this sort of thing at all, given Siri’s lukewarm reception. But this launch is probably more significant as a statement of intent by Microsoft, which is seeking to be the dominant provider of productivity tools on all mobile platforms.

Incidentally Microsoft has also announced the development of a mobile app that turns a standard smartphone into a 3d scanner. The technology is called Mobile Fusion and the resulting scan can be used for 3d printing or for augmented reality. Clever stuff, as shown in the video below.