Well, duh!
If an app is unusable without an IAP, then that tells you about the developer's ethos and what kind of support you can expect. Cancel and delete.
Then I got a call from my Mom: "I typed in the web address, now what do I do?"
To me, it was obvious: hit Enter. But MS had done their A/B testing, and that Go button was for the beginning user.
For the OP to assume that everyone is as adept as they are is folly. As another user lamented, sometimes you have to rub the user's nose in it for them to know they can click something.
Keep in mind that there should be a lockout period where the compressor does not come on within a few minutes of turning off, so you can't just move it back and forth and listen to the compressor start and stop.
No?
Then don’t use my taxes on that!