All the vibrating alarm clocks I could find do not sync with your phone, and have to be set manually. I thought about getting an Arduino, but then I will have to build the whole thing by myself. The only logical conclusion I could come up with is to get a programable vibrator. But most of them are either very expensive of look too much like a vibrator (sus).
This is the closest I got: https://www.amazon.com/dp/B09NNFPHXG https://www.amazon.com/dp/B0CD7FPFQ5?th=1
Hadn’t thought about using a sports watch, will try for sure. ty sir🫡
It has the feature built in. You can get one for about $50 and it works well
Look up the PineWatch. Its as affordable and Open Source as it gets
Love mine, but the motor is a little weak