Reverse engineering Solos smart glasses

Summary

Reverse engineering Solos smart glasses First and foremost: If you’ve got any documentation on this hardware, please contact me! I would love to read the actual specs for this protocol. Background Before the audio-only AI-based smart glasses of today, we’d periodically see companies announcing smart glasses with displays, usually to small fanfare and little success. The Solos Smart Glasses are just another example. Released in 2018, they targeted cyclists and runners. The company itself was spun out of Kopin, which has been making micro-displays for electronic viewfinder and military/industrial HUDs for decades. They cost $500 at time of release and weren’t much of a success, as far as I can tell. Because they weren’t a big hit, I was able to get a new-in-box pair for $30 shipped on ebay. Now, Solos is still making smart glasses, although they’ve pivoted to audio-only AI glasses like everyone else in the world. I emailed support asking for documentation, but they played all cagey (wouldn’t want to tell somebody how to use a product you dropped 7 years ago) and wouldn’t do more than give me the APK for the companion app. I played with the app on a bike ride. As you see in the review I linked above, the glasses cycle through several screens of information as you ride, in a way which I found pretty usable. It also does navigation, but bitrot appears to have set in… it was constantly convinced I had left the route and needed a new route calculated, then when I reached the destination it said “you have arrived” over and over until I shut it down. Yes, you can remove the slightly goofy yellow plastic lenses: Anyway, I don’t really need a wearable bike computer, so I started trying to figure out how I could hack these. Why am I interested? Because I’m interested in displays for wearable computing, and these are both cheap and wireless. Bluetooth capture I guessed that the glasses probably didn’t run a lot of software on-board but instead received bitmaps or vector graphics...