I just wanted to call out how cool it is to replace the guts of a 1980s-era wristwatch with a ARM Cortex M0+ microcontroller, while reusing the original display and buttons.
One of my long-term hacker project goals is to replace the guts of an analog watch with a microcontroller and turn it into a "smartwatch-lite". There's a surprising amount of information and features you can display with three pointers (and a small numeric window): temperature, heartrate and other body sensors, NFC to replace payment or access cards, etc.
Yeah, I had a Withings semismart watch, one of their cheaper models without a screen. It integrated a pedometer, and had a dial had that would show steps taken, it moved from 0 to 100% of your goal. One had to pair it to the Withings Android app to set not just the goal for number of steps/day, but even for setting the time.
I sold it after a few months, realizing how much I missed a second hand and a glow-in-the-dark face. Also, the app had a ton of telemetry going back to Withings.
Building your own you would be in full control of the data.
Yep there are plenty of watches like that (for example Fossil I think), but I'd really like to take a nice vintage watch and build a hackable watch platform myself.
