The Hey+ 1S is the follow-up to the Hey+, which Xiaomi launched very shortly after the Mi Band 3 in 2018. The Hey+ was essentially a design template for the Mi Band 4, so this may well be an early glimpse of the design we could see on the Mi Band 5.
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The differences between the Hey+ 1S and the latest Mi Band seem less significant this time around though. They've both got identically-sized displays for starters with the 1S also featuring a 0.95-inch color AMOLED display.
That screen has been slightly redesigned on the Hey+ 1S, though, bringing a more rectangular look, with rounded off corners and what looks like a capacitative button below the display.
The tracker is waterproofed to 5ATM, which means it's safe to swim with up to 50 metres depth. A major design difference versus the Mi Band 4 lies in the strap. The Hey+ 1S uses a more traditional buckle-style band, whereas the Mi Band 4 has a silicon clasp for adjusting the fit.
In terms of features, the Hey+ 1S covers those activity tracking basics. There's also sleep tracking and heart rate monitoring on board. The ability to view notifications and set up alarms make up its core smartwatch-style features. Everything runs on HeyOS, Xiaomi's custom operating system.
What this tracker does have that the Mi Band doesn't is additional uses for the onboard NFC. It will still let you pay for things and can act as a work card or pass. Additionally though, it can also double as a bus card with compatibility for 248 cities in China.
There's a 120mAh capacity battery that should last 18 days according to Xiaomi. The Mi Band 4 offers up to 20 days of tracking time in comparison.
The Hey+ 1S is available for pre-order in China now, priced at around $25. That also makes it a small chunk cheaper than the Mi Band 4. There's no details whether it will launch outside of China, though we'll update this story if that changes.
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