While Windows 10 is currently rolling out to desktop and laptop computers worldwide, the Microsoft Lumia fans will not be able to enjoy a mobile version of the new software until later this year. However, what we now know is that the company has revealed the first Lumia devices to get the update once Windows 10 Mobile arrives.

Microsoft Lumia 640, 640 XL among the first to receive Windows 10 Mobile update

Fortunately, the Lumia 640 and its bigger sibling, Lumia 640 XL, are included in the first batch of handsets to receive the firmware upgrade. The rest of the list includes the Lumia 430, Lumia 435, Lumia 930, Lumia 532, Lumia 535, Lumia 540, Lumia 735, and Lumia 830. Microsoft is also expected to roll out the update to older models under the Lumia brand, albeit at a later date.

The 5-inch Lumia 640 and the 5.7-inch Lumia 640 XL were both launched back in April this year and made available the following month. Both of the handsets' display is made with IPS LCD screens protected by Gorilla Glass 3. The smaller model packs an 8MP main cam while the XL version is equipped with a 13MP primary camera. Before being treated with a Windows 10 update, the handsets are currently run by Windows Phone 8.1 OS topped with Lumia Denim UI.

Microsoft mentioned that Windows 10 Mobile will offer a handful of new features including new Office apps, an improved Action Center, a more intuitive Cortana, support for universal apps, and a new browser called Edge.

Lumia 950 and Lumia 950 XL release date rumors

Microsoft had previously been speculated to launch the Lumia 940 and 940 XL powered by Windows 10. However, recent reports indicated that the software giant has decided to skip the Lumia 940 line altogether and opt for the "950" series instead.

The duo of upcoming Lumia 950 and 950 XL flagships are reportedly given the code name Talkman and Cityman, respectively.

The smaller Lumia 950 is said to boast an Iris scanner based on biometric technology. It will also pack a 5.2-inch WQHD display, Snapdragon 808 hexa-core processor, 3GB RAM and a 3,000mAh battery.

Meanwhile, the Lumia 950 XL is supposed to arrive sporting a bigger 5.7-inch WQHD display. It will be powered by a 64-bit, octa-core Snapdragon 810 partnered with 3GB and 32GB of built-in storage that's expandable up to 128GB via microSD card.

Located at the back of the Lumia 950 XL is a rumored 20-megapixel PureView main camera with triple LED flash. The purported flagship will be kept running by a removable 3,300mAh battery.

Speaking of the devices' release date, there has been conflicting reports about when exactly Microsoft would launche ts next high-end Windows 10 handsets.

A recent WindowsCentral reports claims that the Redmond-based company will unveil both the Lumia 950 and Lumia 950 XL at a dedicated event that will take place in New York on September or October. That's in contrast to earlier reports suggesting that they will be launched during the IFA 2015 event.

On the other hand, some tech observers suggest the Microsoft may be planning to release the Lumia 950 and 950 XL on October 10-a day that corresponds to the number 10/10 which marks the expected release of the Window 10 OS for mobile devices.