I'm confused about the the following statement in the review guidelines 3.1.1 "Non-subscription apps may offer a free time-based trial period before presenting a full unlock option by setting up a Non-Consumable IAP item at Price Tier 0 that follows the naming convention: “XX-day Trial.” ..." Current situation: This is my first app and not published yet. It's planned to be offered at no cost. I've implemented a non-renewing subscription IAP item to unlock all features for a period of time. The app keeps still useful without buying the IAP item. Questions: What's the meaning of "non-subscription apps"? Does it mean that I am not eligible to offer a free trial period IAP item (Non-Consumable item at price 0)?