I use the Peloton app with a non-Peloton bike. I bought my bike from the Devil Bezos at the end of March. It's by a company called Sunny and it was $400. It's this one.
A gym friend bought another from the same brand that's a bit more high end. Neither of us have had issues. I swapped out the pedals on mine so I can clip in with my spinning shoes.
The Peloton app has a ton of other stuff on it too. I take yoga classes, and they also have strength, meditation, running, walking, bootcamp, and some other stuff I am forgetting about. For $15/month I am so getting my money's worth.