Hacker News Reader

What you could do is have one version for all buying customers, but you have a feature state depending on the purchase date. Customer X buys Version 1.1 on 2024-04-20 and receives all new features until 2025-04-19. after that, bug fixes and new versions are delivered, but new major feature additions require a license renewal after the cutoff date. So, it would be decoupling major features from the app version. I have seen some Apps doing that, for example Halide.

Sketch is a tool used by people 8 hours/day (or at least was). Therefore, their pricing is more accepted by users/customers. In your case, it's not really a tool that one will use daily.

Sletch is a complex app that is used by professionals for 8h a day and costs $99. Your app is not comparable to that, just the pricing model. In relation to Sketch, your app is crazy expensive. I would have bought it for $19.