Microsoft is currently preparing at least three new Windows Phone 8.1 devices for release this year, including a 4.7-inch midrange "Superman" handset, a low-end "Rock" device, and its "McLaren" flagship Windows Phone with the new 3D Touch features. Leaked photos posted to popular Chinese microblogging site Weibo suggest there could be another Windows Phone 8.1 handset on the way, which may fill the midrange gap and replace the Lumia 820. The mysterious device appears to use an aluminum frame with a polycarbonate back, a construction both the Lumia 925 and Lumia 930 use. WPDang speculates that this could be the Nokia Lumia 830. It's also possible this is Nokia's "Tesla" handset, a midrange device that could be dubbed the Lumia 730 when it launches.

The rear of this unknown Lumia also includes a large and flat camera housing, suggesting that it won’t feature the type of 41-megapixel sensor found on the Lumia 1020. Despite Microsoft adding support for on-screen Windows Phone buttons, this handset will include the regular capacitive buttons at the front of the device. While the pictures could be an elaborate fake, a number of Nokia devices have leaked on Weibo previously, including the Nokia X, Lumia 1520, and Lumia 719. We’ve reached out to Microsoft for comment on the photos, and we’ll update you accordingly.