When you are developing apps, you can apply data persistence on object variables. By doing so, the variables are stored on the server and remain intact between sessions. You can choose whether to save the data at the user level or the app level. This means that data can be saved for all users within the program. For example, if a comment text box is included in an app for users to provide feedback, the data entered in this box can be saved and remains persistent throughout the app.
Persisting app data can be done in two stages — managing the internal state and storing user inputs. Read the upcoming sections for more details on these topics.