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
What you are looking for is a “Bed shaker”. These are often used by the deaf to wake up. A relatively cheap phone-connected one can be found here but it’s iphone only. This one works with Android. Both use proprietary apps. The website linked was just at the top of a Google search, you can find stuff like this on Amazon as well.