I'm disappointed I can't find reference schematics for the smartwatch but they provide datasheets and specific chip models at http://developer.sonymobile.com/se

I'm disappointed I can't find reference schematics for the smartwatch but they provide datasheets and specific chip models at http://developer.sonymobile.com/services/open-smartwatch-project/smartwatch-hacker-guide/ http://developer.sonymobile.com/services/open-smartwatch-pro... The watch has bluetooth, a touchscreen, and an STM32F2 microcontroller [disappointed its not a F4 :( ] which makes it a powerful and cheap development kit. Their instructions for flashing the firmware of the chip uses open source dfu-util so IIRC you'll be able to flash a binary to the STM32F2 from any compatible toolchain. Surprise, surprise, this means Arduino from LeafLabs!: https://github.com/leaflabs/www.leaflabs.com/blob/master/posts/major-update-experimental-stm32f2-and-f1-value-line-in-libmaple-master.md https://github.com/leaflabs/www.leaflabs.com/blob/master/pos... Looking at http://www.cmw.me/?q=node/59 http://www.cmw.me/?q=node/59 you could even replace their PCB with your own, preserving the LCD connections and upgrading the processor to an even more power efficient one with a sensor or two added on (this is a four layer board at most, you could theoretically make the ICs even denser). However, you'll probably want to find someone with a pick and place + reflow at a hackspace or something unless you're confident you can reflow leadless chips and 0201 components yourself.