That being said, the folks at GadgetzArena have stumbled across a promotional video posted by Microsoft China which explains the Continuum feature. According to the video’s description, it mentions the various devices that would support Continuum, and they listed handsets like the Lumia 950 and Lumia 950 XL, the Acer Jade Primo, and also the Lumia Phone X.
Note that 3 out of the 4 devices mentioned have been announced and launched, with the Acer Jade Primo being the latest and was revealed at CES 2016 earlier this month. This leaves the Lumia Phone X as the mystery device. Microsoft later went back to edit the name to the Lumia X. If the name had been a mistake, we’re sure it would have been completely removed, but to edit it to the Lumia X suggests that the device could be real.
It is unclear as to what kind of phone the Lumia X could be, but some are speculating that maybe this could be referring to the Surface Phone and the name was used as a placeholder. Either way we are pretty excited and with MWC taking place next month, and with Microsoft Build kicking off towards the end of March, perhaps we will learn more about the device then.