iOS App Store: free limited version of app
You are permitted to have free, lite versions of your app in the App Store.

However, demo/trial versions are prohibited per the App Store Guidelines.


  2.9 Apps that are "beta", "demo", "trial", or "test" versions will be rejected


A far better solution is to offer a full featured free trial and then offer purchase and or subscription to maintain the paid app status.  Watch the 2018 WWDC videos on App Store changes to get details on how a developer might implement this.  On the policy side, this is pretty clear-cut and allowable by Apple.