This is a great teardown, I always admire the HW designers that are able to embed so many IC (especially BGA) into such a small form factor.
How many layers could the main PCB have?
Is it just my browser, or the embedded video is missing?
I am amazed at what they can push onto the PC board.
Can you confirm if the watch was working before disassembly? DId you reassemble the watch and confirm operation?
Was there the usual annoying little coil spring for the piezo buzzer or was another pogo pin used ?
'Couch to 4k(Byte)'