While we're working hard to make Windows 10 available for other Lumia devices, the following is a first list of Lumia smartphones that will receive a free upgrade when available: Lumia 430, Lumia 435, Lumia 532, Lumia 535, Lumia 540, Lumia 635 (1 GB RAM), Lumia 640, Lumia 640 XL, Lumia 735, Lumia 830, and Lumia 930.