When apps are used by users they generate data. Apps typically need access to or save this data in order to function properly, and to provide the best user experience. This includes personal settings including media, as well as other documents. This data can be used to track clicks as well as product purchases made within the app. There are a variety of ways to gather this information, including asking the user for it, or inferring it from on-site behaviour or buying it from a third-party. The ideal customer data should be stored centrally and in a standard format that allows for easy integration and exchange between different applications. There are emerging standards for profiles of customer data by industry sectors that could help define the data models that are to be used.
There are numerous http://www.virtuadata.net/how-to-service-your-own-computer methods to store data, and the storage of data in an app will determine how the user interface presented. The most popular is the storage of files, in which the data is saved as folders and files, arranged in a hierarchy. Hard disk drives as well as cloud storage like Google Drive or Microsoft OneDrive make use of this method. Block storage is another option that divides data into blocks and stored anywhere in the storage infrastructure. They are identified by identifiers that make them easy to find and then act upon.
Early systems came with tools which provided detailed information about the properties and characteristics of storage media in a textual form. Modern systems, like Android and iOS, provide visualisations to support these functions, notably capacity/usage and duration. Capacity/usage visualizations are typically presented as horizontal bar charts, while the duration is represented by a circular pie chart or variants such as doughnut charts.