Stands for "Universal Windows Platform." UWP is an application development platform created by Microsoft. A UWP app can run on multiple devices, including Windows PCs, tablets, and smartphones. Some UWP apps can run on other types of Microsoft hardware including Xbox, HoloLens, and IoT devices.
UWP provides a common platform for developers to build apps for multiple types of hardware. The Universal Windows Platform API includes a wide range of libraries, functions, and user interface elements developers can integrate into their apps. By including multiple DeviceFamily types in a UWP app, a developer can customize the interface of the app for several types of devices.
UWP and the Microsoft Store
When the Microsoft Store (formerly the Windows Store) launched in 2012, developers could only submit UWP apps. Programs built on earlier platforms, such Windows Forms and WPF, were not allowed. To expand the range of apps available on the Store, Microsoft later created "Desktop Bridge," which allows developers to package non-UWP apps for the Microsoft Store.
NOTE: UWP was introduced with Windows 10 and is not backwards compatible. Therefore, UWP apps will only run on PCs running Windows 10 and later, as well as other supported devices.