Microsoft Build 2015: what can we expect?

Microsoft is expected to reveal further details of Windows 10 at its annual Build conference

Microsoft is set to reveal more features of the forthcoming Windows 10, and provide more information on its virtual reality computing headset HoloLens at the firm's annual Build conference.

Microsoft Build is the Windows maker's annual event, and some industry experts are suggesting it could be crucial for the technology giant to introduce appealing new products - as it continues to fight against the dominance of Apple and Android in the mobile industry.

Even in the PC market, an area Microsoft has been synonymous with for 20 years, the firm's Windows software is being outgrown by Apple's Mac laptop and desktop line, which run Mac OS X software.

After a Windows event at the beginning of the year that caught the eye because of the introduction of augmented reality computing with the HoloLens headset, there is growing expectation that Build 2015 will see Microsoft give its products a hard sell.

At that Windows event in January, HoloLens was arguably the biggest announcement. The augmented reality headset Microsoft previewed has been designed to enable users to compute using 3D holograms that appear in front of them, no matter where they are.

While those at that event were able to try a prototype, the first real development version of the device could appear on Wednesday, marking one step closer to retail release.

There is also likely to be an on-stage demo of HoloLens, and possibly some more information on the kind of apps it will support, and how Microsoft envisages them being used on the device.

The most prominent product from Microsoft remains Windows 10. Though a fair amount of the new software has already been revealed, such as the return of the Start menu and Project Spartan; the as yet still unofficial name for the new Windows web browser, there are still plenty of details to discuss.

Top of the list is a release date - which remains "summer", but Microsoft is expected to elaborate on this, as well as give information on when the new operation system will reach devices like the Xbox One and Lumia phones.

Microsoft is also said to be keen to get more Android apps on Windows; and Terry Myerson, the head of Windows, is expected to announce a series of new tools for developers that will make it easier for them to transfer their code from Android to Windows - opening the door for an expansion of the number of apps currently on the platform, which is still some way behind both Apple and Android in number of available downloads.

One such tool Microsoft is rumoured to be considering is a dedicated app to connect iOS and Android devices with Windows 10.

While the Apple App Store and Google Play are both over the 1 million mark, the Windows App Store has around 200,000 apps.

Hardware to house new software is a pressing issue for Microsoft too. A new flagship Windows Phone, to go with Windows 10, could be announced - as well as more Lumia devices designed to run Windows 10.

Some experts believe full announcements on new phones could be held off until Windows 10 is released, but some details or ideas could be forthcoming during the keynote from CEO Satya Nadella.

There are also persistent rumours of Cortana, the Windows digital personal assistant, making the jump to iOS and Android. This would be a disruptive move within the industry as Cortana regularly outperforms Apple's Siri and Android's Google Now in benchmark tests.

Microsoft Build is set to begin at 4.30pm GMT.