What do you like in my first free ebook on Angular, Ionic Framework and Cordova?

I'm in the process of writing my first ebook ever on Angular, Ionic Framework and Cordova. It will walk through the setup steps and micro-example for phone feature such as Camera, GPS, Accelerometer... I found it's hard for beginners to find docs separately for each of the 3 frameworks. So this is more of an integrated place to get into the core.

What topic do you like me to cover?