I am assuming this is what you are referring to when you stated not that detailed:
DIFFERENCES TO THE CLASSIC UI
The differences between Granite UI and ExtJS (used for the classic UI) are also of interest:
ExtJS Granite UI
Remote Procedure Call State Transistions
Data transfer objects Hypermedia
Client knows server internals Client does not know internals
"Fat client" "Thin client"
Specialized client libraries Universal client libraries
Well ExtJS is based on the ExtJS framework. http://www.sencha.com/products/extjs
Grainte is based on the coral-ui http://docs.adobe.com/docs/en/cq/5-6-1/touch-ui/coral-ui/
Granite touch UI is the the API to use when building components for AEM touch UI. ExtJS is used in Classic UI.
Here is a community article to get you up and running with Touch UI:
Creating your first Adobe Experience Manager Touch UI component
You will build your first Touch UI component, the dialog and place the component on the Touch UI side rail.
When developing with the Touch UI - you will notice some difference from ExtJS - for example - the way you build dialog boxes for components is different.
At the end of April - we will be having an Ask the AEM Community Experts around Touch UI.
The signup will be posted soon in these forums.