Introduction: Storage, Caching, and Offline

A user can lose a connection or close an app while work is still in progress. Storage and synchronization determine what the app can recover afterward.

Imagine writing a note on a train. The text appears immediately. Does that mean it is saved? Can another device read it? What happens if the app stops before the next request finishes?

This chapter explains how to answer these questions with clear product behavior and a recoverable client design.

Separate three promises

Visible means that the UI displays the text. The text may exist only in memory.