When users interact with apps they generate data. This is the data apps usually require to save or access in order to function properly and offer the best user experience. The data can include personal settings as well as media, among other documents. It can also be used to monitor clicks, purchases and other conversions within the application. The data can be gathered by a variety methods, including by asking the user, using the assumption that it is based on their behavior on site, or by purchasing it from an outside. Ideal customer data should be centrally stored and in a standard format that permits easy integration and exchange between applications. There are emerging standards for customer data profiles according to industry sectors that can aid in defining the data models to use.
There are a variety of ways to store data and the system used in an application will impact how the user interface looks. The most common is the storage of files, in which the data is kept in folders and files that are arranged in an order. Hard disk drives as well as cloud storage such as Google Drive or Microsoft OneDrive utilize this method. Another method is block storage, which is where the data is split into blocks that can be stored anywhere on the storage infrastructure with identifiers to allow them be quickly identified and taken action.
The first systems had built-in tools that provide detailed information about the properties of the storage medium in a textual format. Modern systems, such as Android provide visualisations of these functions, including capacity/usage as well as lifetime. The visualisations for capacity/usage are usually horizontally stacked bar charts. Lifespan is typically shown in a circular pie chart as well as its variants such as doughnut charts.
