The first smartphone carrying Windows Phone 8.1 starts shipping this week in Asia, even as Microsoft continues tweaking that latest version of its mobile OS.
The device is the Nokia Lumia 630, which also comes in a dual-SIM (subscriber identity module) version and which will be sold later in Europe and the U.S. It features a ClearBlack 4.5-inch LCD screen with Corning Gorilla Glass 3 and a quad-core Snapdragon processor.
It also comes with SensorCore, a feature that lets the devices monitor users' movements without draining the battery and which can be used in conjunction with fitness-tracking apps, according to Microsoft.
However, what sets it apart at the moment is the distinction of being the first commercially available smartphone running on Windows Phone 8.1, according to Microsoft.
The new version of the OS comes with the voice-operated assistant Cortana, Microsoft's answer to Apple's Siri and Google's Now, as well as with a new "Action Center" for easier management of device functions and notifications, and improvements to its calendar, music, video, podcast and other features.
The standard Lumia 630 model is expected to cost around a!119, or about $163, before taxes and subsidies, while the dual-SIM model will go for around a!129, or about $176, according to a Nokia blog post.
Since April, anyone has been able to install a developers' preview version of 8.1 on Windows Phone devices, and Microsoft this week also rolled out an update of the OS with new features and bug fixes, Microsoft official Brandon LeBlanc said in a blog post.
"We've received a ton of great feedback so far on what people like about Windows Phone 8.1, and some things we can improve," he wrote.
The "baked" version of Windows Phone 8.1 shipping with the Lumia 630 is considered finished because it includes the OS along with additional software from Nokia and from the mobile operators that will carry it, a source close to the company said.
Meanwhile, the Windows Phone 8.1 developer preview isn't considered finalized because it hasn't gone through carrier testing and does not include software enhancements from Nokia, this person said.
Microsoft didn't immediately respond to a request for comment.
Juan Carlos Perez covers enterprise communication/collaboration suites, operating systems, browsers and general technology breaking news for The IDG News Service. Follow Juan on Twitter at @JuanCPerezIDG.