For the person who builds the app. This page says what SmartApps put in your hands, what stays with other roles, and how a week runs.
Formulas cover conditions, calculations, dates, text and lists; scripts and REST calls are registered once by the app team as functions you call by name.
The validator refuses a save that references a missing field or removes a handler a screen uses; the preview holds writes; the publish gate needs the owner's approval.
The documentation's configuration guide, the 30-minute first-app walkthrough and the catalogue entries, each a worked example.
Tell us your role and one process; the demonstration runs the screens you would use, on data like yours.