Apple takes 30% via IAP

The fix

Three legal options: (1) Stay in IAP — simplest, pay the tax. (2) Subscriptions get 15% after year 1 if you stay on IAP. (3) For digital subscriptions outside the app (link from your website), you keep 100% — Apple's recent ruling allows linking out. SaaS-shaped apps usually have customers sign up via web, then use the app.