Drupal can be used as a pluggable backend using just about any API you can think of. By integrating with these APIs you can build just about any business apps you would find on the App Store or Google Play.
Drupal is a monolithic architecture yet is mature and feature-complete, this includes the theme layer.
There is increasing interest in replacing the theme layer with decoupled architecture using a JS framework.
These frameworks can greatly enhance a website's "app-like" behavior. Still, increasingly there are more options available for making your website app-like without the extra commitment and pitfalls that come with a fully decoupled architecture.
There are pros and cons of using the Drupal theme layer, in particular, we will discuss how you can make a Drupal-powered website "feel like an app." We will compare which web capabilities can be used for decoupled vs coupled and explore options for a "hybrid" approach.
Building a web app that is responsive, fast, and looks and feels like an app is possible with the theme layer. At times this web experience can even improve what users are used to in a native app or frontend framework because it "just works."
There are a variety of modules, techniques, and libraries that can be used to enhance the app-like functionality of a coupled Drupal install. We will go through examples and demos of each of these capabilities.