640-XLFeat-1Lumia 640 and Lumia 640 XL are receiving a software update that includes new firmware and OS versions. As I write this post my new Lumia 640 XL is already downloading the update. Latest software release for both Nokia Lumia 640 and Lumia 640 XL is Lumia Denim firmware 02177.00000.15184.36xxx and Windows Phone 8.1 GDR2 version 8.10.15148.160.

Lumia 640 Changelog :

Voice over LTE support enabled for selected operators.
Native Wi-Fi calling support enabled for EE  UK and T-Mobile USA.
Additional improvements to stability, audio quality, Wi-Fi and cellular connectivity, national roaming, and more.

Lumia 640 XL changelog:

Voice over LTE support enabled for selected operators.
Native Wi-Fi calling support enabled for EE UK.
Additional improvements to stability, audio quality, Wi-Fi and cellular connectivity, national roaming, and more.

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