New part of the day: hackable smart ring

We’ve seen a prolific firmware hacker (Aaron Christophel) tackle all kinds of smart devices and he never disappoints. This time, he examines a device that seems to come from the pages of the Cyberpunk RPG manual – a shiny, chrome Bluetooth Low Energy (BLE) smart ring, equipped with sensors, relatively hacker-friendly and currently selling for as little as $20.

The ring’s design is simple – the exterior is polished anodized metal, with the electronics and battery neatly arranged along the interior surface, as well as a magnetic charging port. It has a BLE-enabled MCU, a heart rate sensor, and an accelerometer. It’s not much, but you can do a lot with it, from regular exercises and sleep tracking, to a touch-sensitive interface, to anything you want to control from the palm of your hand. In the comments of the video, someone noted how the ring’s custom firmware could be used to detect seizures; a perfect example of how hacking such gadgets can give someone a better future.

The ring’s manufacturer’s website has firmware update images, and it turns out you can flash your own firmware onto it wirelessly via BLE. There’s no signing or encryption – it’s the perfect device for your purposes. Moreover, the MCU is quite well known. To get started, there’s an SDK and datasheet that describes everything you’d ever want to know, except perhaps the most delicious features. It has 200K RAM, 512K flash memory, BLE library already in ROM, this ring gives you a lot of possibilities even though it takes up little space. You can even access the Serial Wire Debug (SWD) pads of the chip, but you’ll need to scrape off some epoxy first.

As we’ve seen in the past, when (Aaron) starts hacking these types of devices, their popularity tends to skyrocket. We recommend ordering a few now before retailers wise up and start raising prices. While we’ve seen hackers build their own smart rings, it’s a difficult task and the end results are usually very limited. The potential to create your own firmware for such an inexpensive and powerful device is very exciting – watch this space!

Thank you (linalinn) for sharing this with us!