Ever since Microsoft first unveiled Cortana as part of Windows Phone 8.1, there’s been speculation that the company might bring its digital ‘personal assistant’ to other operating systems. Indeed, it has seemed almost inevitable, given Microsoft’s growing focus on making its products and services available across multiple platforms.

In November, Microsoft’s chief experience officer and former head of Windows, Julie Larson-Green, was asked directly if Cortana might make the move to non-MS platforms. Her response: “The short answer is, yeah.”

So it should come as no great surprise to hear that Microsoft is indeed planning to bring Cortana to rival operating systems, as Reuters reports. While Cortana will remain a tightly integrated component in Windows on PCs, phones and other devices, the company is planning to making the assistant available as a standalone app on Android and iOS.

The effort to extend Cortana’s reach across multiple platforms is being developed with knowledge from ‘Project Einstein’, a Microsoft research project focusing on artificial intelligence. More than simply bringing access to its assistant to other app stores, Microsoft has been working on a ‘more advanced’ version of Cortana as part of its cross-platform efforts, using the AI research from Einstein.

Eric Horvitz, managing director of Microsoft Research, and part of the Einstein team said: “This kind of technology, which can read and understand email, will play a central role in the next roll out of Cortana, which we are working on now for the fall time frame.”

The aim is to build on Cortana’s existing feature set – and particularly the ‘personal assistant’ elements, such as diary management, recommended leisure activities, and proactive traffic and public transit updates. While Siri is well versed at responding to basic requests, and Google Now surfaces ‘cards’ of information that it believes will be helpful to the user, Microsoft intends to extend the personal assistant functionality much further, developing an even more capable Cortana that can reliably anticipate a user’s needs – on any platform.

Horvitz explained: “We’re defining the competitive landscape… of who can provide the most supportive services that make life easier, keep track of things, that complement human memory in a way that helps us get things done.”

But in order to build this platform, Microsoft needs more data, more users, more availability. While Windows 10 will extend the reach of Cortana considerably when it launches later this year, Microsoft wants to put its assistant into the hands of as many people as possible. The more people using the assistant, the more data its machine learning platform can gather to help improve the system even further for everyone.

Even so, the decision to make Cortana available on other platforms is unlikely to go down well with many Windows users, as some believe that Microsoft should keep such features exclusive to its own operating systems.