Following updated guidance and changes from Apple and Google about apps submitted through their respective platforms, both started to reject new app submissions that continued to use the UIWebView option.
In a recent platform update, we have upgraded to the newest option which is supported by Apple and Google for app submissions which is the WK WebView option.
If you get a rejection message from either store about this, please ensure that you regenerate your application and download the latest version of your app from the platform before trying to resubmit a new version for their review.