While not the most glamorous component of an application's user experience, form screens are a long-time staple of software. A form screen can be defined as any screen where the user is expected to explicitly enter or change data, as opposed to viewing or navigating it. Good examples of form screens are login screens, edit profile screens, or the add contact screen from a phonebook app. Over the years, the idea of what constitutes a good form screen has changed, with some people going as far as to shun them completely. However, you can't capture the user's data out of thin air.
The Android standard toolkit provides an excellent and diverse collection of widgets and layout structures to facilitate building excellent forms, and in Material Design applications, form screens can often double as a view screen (what will usually be a read-only version of the form screen) thanks to the placement of labels. A good way to understand this principle is to consider the evolution...