Windows 10 was released as a new era for the Windows operating system, bringing back the start menu button and introducing new features like Cortana, Windows Hello, and Microsoft Edge browser. It was made available across several editions for different user types and also optimized for touch, keyboard, and mouse. Within 24 hours of release, Windows 10 was activated on over 14 million devices and by January 2016 it had been installed on more than 200 million devices globally. This increased the demand for Windows apps and created opportunities for Windows app development companies.