Xiaomi's Senior VP, Hong Feng, confirmed last month that the company is already working on the MIUI 10 update, and now an unofficial list of smartphones which will receive that update has surfaced. Back in November last year, the company had confirmed that MIUI 9 will be the last update for the Xiaomi Mi 2, Mi 2S, Redmi Note 4G, Mi 4i, Redmi 2, Redmi 2 Prime and the Mi Note devices.
Having said that, if today's info is accurate, MIUI 10 will be reaching the following phones: Mi 3, Mi 4, Mi 5, Mi 6, Mi 5s, Mi 5s Plus, Mi 4s, Mi 4C, Mi MIX, Mi MIX 2, Redmi Y1 / Lite, Mi Note 2, Mi Note 3, Redmi Note 3 / Pro, Redmi Note 4 / 4X, Redmi 5 Plus, Redmi 5, Redmi 5A, Mi 5X, Mi Max, Mi Max 2, Redmi 4 / 4X /4A, Redmi 3 / 3S / Prime, Redmi Pro and Redmi 3X. If this list is accurate, and it may be, at least to a certain degree, Xiaomi will be bringing MIUI 10 to quite a few devices, which was to be expected. The company has been updating a ton of devices to MIUI 9, including even some devices which are 4-5 years old, so this list is not exactly surprising, though the company has to stop updating its oldest smartphone at some point, and it seems like the time came. It is worth noting that it is still unknown whether the next update will be marketed as MIUI 10 or MIUI X, as Xiaomi actually asked its consumers for an opinion on the matter quite recently.
We do not really have any info when it comes to MIUI 10 at this point, all we know is that it's coming, as per the company's confirmation, and that's pretty much it. MIUI 9 introduced some visual changes to the company's skin, along with a number of new features, and MIUI 10 will probably do the same, unless the company decides to completely revamp its skin, of course, though that probably won't happen. It is still unknown when will MIUI 10 become official, but MIUI 9 was announced back in July last year, so it's possible that MIUI 10 will land in mid-2018. Xiaomi did not start pushing a global version of MIUI 9 until November last year, however, so those of you who run global ROMs on your phones will probably have to wait quite a bit in order to get the update.