Microsoft has started rolling out Denim, its latest Windows Phone firmware for Lumia devices. Among the new features heading to Microsoft mobiles are an updated Lumia Camera and Cortana.
While newer devices like the just-announced sub-$100 Lumia 435 and Lumia 532 are shipping with Denim installed already, older devices should begin seeing the update become available soon, according to Microsoft.
Microsoft had hoped to release the update before the beginning of 2015 but said on its Lumia blog that Denim "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 following partner testing and approvals," it added.
Depending on the carrier, other phones that already have Denim include the Lumia 520, Lumia 535, Lumia 620, Lumia 625, Lumia 720, and Lumia 930.
Owners can check update information for their region here, though Microsoft doesn't detail exactly when each device will get the update.
Denim expands the availability of Microsoft's personal assistant Cortana, which is a beta product in China and the UK, and an alpha in Australia, Canada, France, Italy, Germany, and Spain.
Thanks to SensorCore technology, users of the the Lumia 930, Lumia Icon, and Lumia 1520 will be able to activate Cortana when the device is idle by saying, "Hey Cortana".
Other key feature updates include the ability organise apps into folders, which Microsoft calls Live Folders; and an updated Glance Screen that now shows health and fitness activity from the MSN Health and Fitness app along with other lock screen content when the phone is on standby.
Denim also brings an improved Internet Explorer mobile browser and delivers a consumer version of its virtual private network.
One highlight of the Denim update is the effort Microsoft put into the Lumia Camera, adding features such as faster burst shots that can be taken at a rate of one every 42 milliseconds. The new Lumia Camera app will be included in the update for the Lumia Icon, Lumia 1520, Lumia 930, and Lumia 830.
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