Xiaomi's Mi Mix 3 has now been joined by a 5G variant in the UK, and so our attention naturally turns to what comes next. In previous years Xiaomi has announced two Mi Mix models per year in a sort of tick-tock cycle: a major upgrade toward the end of the year, followed by an 'S' model in Spring that improves performance and a handful of features within the phone. The Mi Mix 2S, for example, added to the Mi Mix 2 a faster processor, enhanced photography features and wireless charging.

In 2019 the updated model was been a 5G variant, so due next is Mi Mix 4. And it could be coming very soon, with Xiaomi CEO Lei Jun confirming that a second 5G phone will be coming in the second half of the year, and a mystery 5G device dubbed M1908F1XE recently passing through China's Ministry of Industry and Information Technology (MIIT).

The inclusion of 5G confirms it is a flagship, but Mi 10 isn't expected until February, so the smart money is on Mi Mix 4.

When is the Mi Mix 4 coming out?

Mi Mix 4 release date: October 2019 (TBC)

Judging by previous years, we anticipate Mi Mix 4 will be announced in October.

How much will the Mi Mix 4 cost?

Pricing typically stays pretty constant with Xiaomi devices, so where the Mi Mix 3 is priced at £499 (see best Xiaomi deals) we'd expect the Mi Mix 4 to also cost circa-£500.

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What to expect from Mi Mix 4 - features & specifications

A research note from Hong Kong's GF Securities points to a Qualcomm Snapdragon 855, three rear cameras and a periscope lens (which allows for greater optical zoom) for the Mi Mix 4. We've actually already seen this chip introduced in Mi Mix 3 5G, but it's possible the next Mi Mix will in fact get the Snapdragon 855 Plus.

In Mi Mix 2S Xiaomi also added a second lens to the rear camera assembly, so it's not out of the question for it to add a third lens in Mi Mix 3S.

Also tipped for the next Mi Mix is a foldable screen, and Xiaomi is indeed said to be working on such a device with renowned tipster @evleaks sharing a video of a foldable Xiaomi phone/tablet (below) but unable to vouch for its authenticity. 

Neither do we expect to see the in-display fingerprint sensor brought in with the Mi 8 Pro added to the Mi Mix 4: not only would it add to the cost, but we imagine that it would be less compatible with the current sliding-screen mechanism.

That is, of course, if the sliding screen mechanism stays. We know that Xiaomi is also experimenting with under-display camera technology, which allows the selfie camera and full-screen display to co-exist harmoniously. And, of course, we've since seen a pop-up selfie camera in Xiaomi's Mi 9T.

Xiaomi Under-Display Camera Tech

If it does stay the sliding screen may see some new functionality and fine tuning, but in other respects the Mi Mix 4's specification is expected to be very similar to that of the Mi Mix 3. 

So, you should expect to find a 6.39in Full-HD+ AMOLED screen, MIUI, 6GB of RAM as standard with 8GB- and 10GB RAM options available, 128- or 256GB of non-expandable storage, USB-C (for audio, data transfer and charging), a circa-3,200mAh battery, a rear fingerprint sensor and a 24Mp + 2Mp dual-lens selfie camera. 

We'd also expect the dedicated button on the left edge for calling up the Mi AI voice assistant (or the Google Assistant on UK models) to remain.

A tweet that does not reveal its source points to an upcoming Xiaomi phone codenamed Hercules that may or may not be the Mi Mix 4.

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