I've been interested in the idea of a treadmill to walk while at my standing desk as well. Can you share details on the one you have?
The app is really crappy, and I wasn't able to connect it to my phone. But the pad itself does its job so I'm happy about it.
I mostly do 3.5 km/h, you can go faster than that, but then it becomes more difficult to really get work done.
The following article really inspired me to take the step: https://writings.stephenwolfram.com/2019/02/seeking-the-prod...