I have the Amazfit watch as well, and one of the best things about them is that you can use GadgetBridge (Opensource app for Android) in case you don't want to get entrenched in their ecosystem.

You can update the firmware, install watchfaces and have nearly 100% functionality.

There's also https://watchface.zepp.com and the corresponding docs https://docs.zepp.com/docs/guides/tools/watchface/guides/cre...

You still need to generate images for use in that tool.

Developer documentation for the Amazfit device's "Zepp OS" appears to be hosted at https://developer.zepp.com/os/home.

They're absurdly cheap for a device with specs like these. I picked one up off Amazon, along with a small selection of aftermarket metal and nylon-weave bands. It's been years since I bothered wearing any kind of bracelet, and the fetish for expensive watches as conspicuous display of debt-financed pretense of wealth passed me by, but a bracelet topped with a cute little OLED touchscreen, bristling with sensors, and powered by what appears to be an extremely open and friendly programming environment? That's worth the trouble of reaccustoming myself to a somewhat unfashionable accessory.

(Make sure there isn't a space in the simulator executable's pathname. Also note that, because the Band 7 runs Zepp OS 1.0, you won't be able to use any feature that's documented as requiring an API_LEVEL, i.e. OS 2.0 or higher. That's probably part of why these are so cheap, but if they're as flexible as I get the sense from these docs they may be, I'll be upgrading pretty soon to something much more capable like a T-Rex 3.)

The price and capability is really surprising. But the most surprising and welcome thing for me is the long battery life.

Cool. I have this band and I didn't know there was a way to put custom faces on it

It could be easier. Also the tools are quite unrefined. But I can say the same about any other Dev tools these days.

How do you get your data off it?

The data is synced with Health app on iOS, and to its own Zepp ecosystem app. You could also write your own app to exfiltrate the data over Bluetooth.

Does anyone have something like this for Xiaomi Band? I have one but the stock faces are an assault on my aesthetic sensibilities.

Edit: apparently there is an app called EasyFace, but it doesn't seem to be open source, and it says it needs to be run with admin privileges. TL;DR: nah, man, I'm good.

Do they have a watch face section in their official app? Just yesterday the watch face in my post was added to the official Amazfit watch face store in their Zepp app. Perhaps Xiomi have something similar.