In the app they have a signature drawing controller, which loads signature.html in webview. The html has Ti.App.addEventListener & Ti.App.fireEvent to communicate between webview and controller. HTML gives error on Ti accessing in html. This is happening in iOS 11.3 beta 1 & beta 2.
Code works fine on iOS 11.2 and earlier
Steps to recreate:
run project on simulator for iOS 11.3
Drawable canvas and text turn green.