The short version
Cotera Hub is a training log. You build a program, log your sets and reps, and see your volume by muscle group over time. All of that lives on your device. There's no Cotera Hub account and no analytics or advertising SDKs, and the publisher has no server that receives your training data.
This policy explains what the app handles, where it is kept, and the few cases where information reaches the publisher, Liam Brooks.