Microsoft is rolling out the latest Windows Phone 8.1 update (Denim) to Lumia devices. The Lumia Denim update brings new features for work and play. It improves Cortana, which will now be available - besides the U.S. - in China and the UK in "beta" and in "alpha" in Australia, Canada India, France, Italy, Germany and Spain. Cortana sees enhancements in natural-language scenarios, offers snooze times for reminders, and you'll be able to chat with her in your car via car-kit integration.

Cortana will be activated by saying "Hey Cortana" while the Lumia phone is in an idle state. This feature will be available for Lumia 930, Lumia Icon and Lumia 1520.

On your Start screen, you'll be able to organize your most-needed apps into folders (such as "News" and "Games") so you can access them with one tap.

The newly updated Glance Screen will also be able to show fitness and other health-related activity from MSN’s Health and Fitness app.

The Denim update also brings an improved IE along with support for consumer VPN.

The owners of the Lumia Icon, Lumia 1520, Lumia 930 and Lumia 830 will also get an updated Lumia Camera, delivering high-quality images at the fastest speed with only milliseconds between shots. Lumia Camera also comes with Moment Capture and Rich Capture.

The Lumia Denim update has started rolling out to a limited number of devices in selected markets and will continue arriving in waves by device. A wider rollout of Lumia Denim to all Lumia smartphones running Windows Phone 8.1 is expected to begin this month.