Users generate data as they interact with apps. Apps often need to access or save this data in order to function properly, and provide the best possible user experience. This data includes personal settings as well as media and other documents. It can be used to track the number of clicks, purchases, and other conversions within the application. This information can be obtained through a variety of methods, including by asking the user for it, using the assumption that it is based on their online behavior, or purchasing it from a third-party. It is ideal that customer data is centrally stored and saved in a standard format to facilitate the exchange of data between applications. There are currently emerging customer data profile standards by industry to help define the data model to use to achieve this goal.

There are a variety of ways to store data and the system used by the application will influence how the user interface looks. File storage is the most commonly used, where data is stored in files and folders that are organized in a hierarchical manner. Hard disk drives as well as cloud storage such as Google Drive or Microsoft OneDrive employ this method. Block storage is a different approach that divides data into blocks and then placed anywhere in the storage infrastructure. They are identified by identifiers to make them easy to locate and to act upon.

Early systems came with tools which provided detailed information about the properties of storage media in textual form. Modern systems, like Android, provide visualizations for these functions, including capacity/usage and lifespan. The visualizations of capacity/usage are typically displayed as horizontal stacked bar charts, whereas lifespan is represented by a circular pie chart or variants, such as doughnut charts.

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