Cheap and working smartwatches for 25$ already exists, they are flooding the markets of developing countries and they are of a OK quality for a smartwatch, they mostly originate from Shenzhen China, problem is there are no software engineers to hack these smartwatches and pair them with open source software instead of chinese spyware smartphone apps.
I've got myself one of these watches hoping I can learn to program something for it, After extracting the facecwatches I found out those were binary files, After many hours searching the internet for help or people who might have already hacked them. I've given up because I knew that even If I start learning assembly, there is no guarantee that I can build my own watch faces using that knowledge, it's a shame cause Chinese gadget are a treasure trove for hackers and people looking for good deals.