If you have not yet upgraded to Windows 10, chances are you are not planning to do so any time soon, if indeed ever. Those of you who do, will probably want to do so before this Friday (29 July), when Microsoft's free update offer ends.

After that, you will be charged £99 ($119) to upgrade to Windows 10.

Microsoft's free Windows 10 update programme should have been a nice bit of PR for the company, but somehow Microsoft managed to turn it into the opposite.

According to the company's own estimations Windows 10 is now running on 350 million devices, indicating that all that incessant pestering had some effect. The operating system isn't on track to hit one billion devices by 2018 as Microsoft initially envisioned, but it is still the strongest start to a Windows operating system to date.

The end of Microsoft's free upgrade offer coincides with the launch of the Windows 10 Anniversary Update on 2 August. Alongside tighter security and deeper Cortana integration, the update introduces new features like Windows Ink, which lets you doodle on your desktop and brings handwriting features to programmes like Office and Microsoft's Edge browser.

For gamers, the Windows 10 Anniversary Update brings Xbox Play Anywhere into the fold. This will allow users with both an Xbox one and Windows 10 PC to begin a game on one platform and then continue it on another.

Budding developers will also be able to try out the new Dev Mode app for Xbox One, which lets users turn their console into a development kit for Universal Windows Platform (UWP) applications.