## polyfills.js 
Contains all polyfills needed to work on the largest range of devices. This is the default polyfill. 

##### Targets: 
- Android 4.4.2 and above
- iOS back to iOS 8

##### Includes:
- All ES6 features
- zone.js
- ES7 reflection


## polyfills.modern.js
A limited of set of polyfills to work on more modern browsers. This file limits the number of ES6 polyfills which are already natively included in modern browsers.

##### Targets: 
- Android 5.0 and above
- iOS 9 and above

##### Includes:
- zone.js
- ES7 reflection, 
- ES6 polyfills, except for:
new regexp features,
math features,
symbols,
typed arrays,
weak maps / weak sets


## polyfills.ng.js
Only the required polyfill for Angular 2. This does not come with any ES6 polyfills. Note that all polyfill files listed here included the required polyfills for Angular 2 to work correctly.

##### Targets:
- Android 5.0 and above
- iOS 10 and above

##### Includes:
- zone.js
- ES7 reflection


## ECMAScript 6 Compatibility

To easily judge which polyfill you may need you can check this [ES6 support table](https://kangax.github.io/compat-table/es6/).