Amazon.com: Microsoft Nokia Lumia 640 LTE RM-1072 8GB 5" Unlocked GSM Windows 8MP Camera Smartphone - Black - International Version No Warranty : Cell Phones & Accessories
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Microsoft now enabling native Wi-Fi calling, HD Voice on the Lumia 640 and Lumia 640 XL | Windows Central
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Lumia 640 & Lumia 640 XL receive new Firmware + OS update. Changelog. - Nokiapoweruser
Lumia 640 LTE RM-1072 - egy ChimeraTool által támogatott Nokia model