Cordova white screen of death iOS - browserify, react, cordova - ios

Question

I have a strange situation with a project for iOS.
Its created using browserify and React for Cordova and aimed at iOS.
We have built the project for iOS using Cordova commands without any issues. It runs with no xcode errors or Javascript errors either however none of the JS ui appears on screen. We just get a blank white screen with the system bar at the top. See attached screen shot.
So far we have found out that if you add HTML to the index.html in WWW folder it prints that fine so I assume its the JS.
When we run in a browser it works as well as building for Android.
We have no problems with anything other than iOS (simulator and device build).
hopefully someone can help me out here because I'm stumped. Please let me know what files you need to look at and I'll make them available.
Thanks in advance.
IMAGES
The error screen: http://www.voidapplications.co.uk/errorScreen.png
What we expect to be shown: http://www.voidapplications.co.uk/whatWeExpect.png

Answer 1

If you are using internationalization component that's because you need to use the Intl polyfill:
Intl.js and FT Polyfill Service
Intl.js polyfill was recently added to the Polyfill service, which is developed and maintained by a community of contributors led by a team at the Financial Times. It is available thru cdn.polyfill.io domain, which routes traffic through Fastly, which makes it available with global high availability and superb performance no matter where your users are.
To use the Intl polyfill thru the Polyfill service just add one script tag in your page before you load or parse your own JavaScript:
<script src="https://cdn.polyfill.io/v1/polyfill.min.jsfeatures=Intl.~locale.en"></script>
When specifying the features to use thru the polyfill service, you have to specify what locale, or locales to load along with the Intl polyfill for the page to function, in the example above we are specifying Intl.~locale.en, which means only en, but you could do something like this:
<script src="https://cdn.polyfill.io/v1/polyfill.min.js?features=Intl.~locale.fr,Intl.~locale.pt"></script>
note: the example above will load the polyfill with two locale data set, fr and pt.
This is by far the best option to use the Intl polyfill since it will only load the polyfill code and the corresponding locale data when it is really needed (e.g.: safari will get the code and patch the runtime while chrome will get an empty script tag).
source & other ways to include Intl polyfill: https://github.com/andyearnshaw/Intl.js#getting-started

Answer 2

You can debug the UIWebView in the simulator with Safari http://moduscreate.com/enable-remote-web-inspector-in-ios-6/. You'll probably see a big error message in the console, if not you will have access to the debugger so you can step through and sort it out.

Answer 3

I have had this issue in the past, it turned out to be unsupported javascript features. for example, setting default parameters in the function. I.e:
function test( myvalue=0 ) { /* ... */ };
I had to initialise the value inside the function instead. You could also try removing any ecma script 2016 features you may have implemented.
Trouble shooting this type of issue was painful. I created a minimal version of the smallest part of my product compiled and ran it on ios emulator, added another chunk of the product, rinse and repeat.
Im sure there's a better way to detect these issues, but I do not know it.