Please look at ionic framework’s overview http://ionicframework.com/docs/overview/
Ionic is based on Phonegap, which is a cross platform technology that helps you build easily mobile applications. Another adventage of it is that you write your code in angularJS.
That means, when you say you want to know the features ionic supports, it is like writing your website using any other plugins. Do some reading about Phonegap to know about the differences between each operating system and what are the quirks in each one of them.
Also, take a look at what other beginers like you were asking lately:
Hope this helps 