Last year, we’ve featured a super cheap smart ring – BLE, accelerometer, heart sensor, and a battery, all in a tiny package that fits on your finger. Back when we covered it, we expected either reverse-engineering of stock firmware, or development of a custom firmware outright. Now, you might be overjoyed to learn that [Wesley Ellis] has written a Python client for the ring’s stock firmware.

Thanks to lack of any encryption whatsoever, you can simply collect the data from your ring, no pairing necessary, and [Wesley]’s work takes care of the tricky bits. So, if you want to start collecting data from this ring right now, integrate it into anything you want, such as your smart home or exoskeleton project, this client is enough. A few firmware secrets remain – for instance, the specific way that the ring keep track of day phases, or SPO2 intricacies. But there’s certainly enough here for you to get started with.

This program will work as long as your ring uses the QRing app – should be easy to check right in the store listing. Want to pick up the mantle and crack open the few remaining secrets? Everything is open-source, and there’s a notepad that follows the OG reverse-engineering journey, too. If you need a reminder on what this ring is cool for, here’s our original article on it.

We’ve seen prolific firmware hacker [Aaron Christophel] tackle smart devices of all sorts, and he never fails to deliver. This time, he’s exploring a device that seems like it could have come from the pages of a Cyberpunk RPG manual — a shiny chrome Bluetooth Low Energy (BLE) smart ring that’s packed with sensors, is reasonably hacker friendly, and is currently selling for as little as $20.

The ring’s structure is simple — the outside is polished anodized metal, with the electronics and battery carefully laid out along the inside surface, complete with a magnetic charging port. It has a BLE-enabled MCU, a heartrate sensor, and an accelerometer. It’s not much, but you can do a lot with it, from the usual exercise and sleep tracking, to a tap-sensitive interface for anything you want to control from the palm of your hand. In the video’s comments, someone noted how a custom firmware for the ring could be used to detect seizures; a perfect example of how hacking such gadgets can bring someone a brighter future.

The ring manufacturer’s website provides firmware update images, and it turns out, you can upload your own firmware onto it over-the-air through BLE. There’s no signing, no encryption — this is a dream device for your purposes. Even better, the MCU is somewhat well-known. There’s an SDK, for a start, and a datasheet which describes all you would want to know, save for perhaps the tastiest features. It’s got 200 K of RAM, 512 K of flash, BLE library already in ROM, this ring gives you a lot to wield for how little space it all takes up. You can even get access to the chip’s Serial Wire Debug (SWD) pads, though you’ve got to scrape away some epoxy first.

As we’ve seen in the past, once [Aaron] starts hacking on these sort of devices, their popularity tends to skyrocket. We’d recommend ordering a couple now before sellers get wise and start raising prices. While we’ve seen hackers build their own smart rings before, it’s tricky business, and the end results usually have very limited capability. The potential for creating our own firmware for such an affordable and capable device is very exciting — watch this space!

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