Windows Phone 8.1 is at the end. Around three years after the release of the update Microsoft stopped the support at the end of the last day. Updates, also security-critical, are no longer available. Who owns a smartphone, which has not received an update on Windows 10 Mobile, is on the siding.
Available is the update to Windows 10 Mobile for Lumia Icon, 1520, 930, 640, 640XL, 730, 735, 830, 532, 535, 540, 635 1GB, 636 1GB, 638 1GB, 430, 435, BLU Win HD w510u, BLU Win HD LTE x150q and MCJ Madosma Q501.