The app's premium unlock appears to be a $6 one-time purchase. Given that it's not a consequential life decision, the way a subscription can sometimes be, I would rather normalize paying for software that is well-made and lovingly maintained instead of having everything be free but it falls into disrepair after some big Apple update because it's too hard to justify working on it anymore.

I have a harder time with software that I have to sign up for a "trial" of a $20 monthly subscription before I can really experience what it's like to use it. With this app, you can see exactly how it works during the daytime at least, and what settings you'd be able to use once you pay, and no trial hanging over your head.