Fedora 22 is going to require applications that want to appear within their GNOME Software Center to ship an AppData file, which is a meta-data specification for providing basic data about the program. AppData is a GNOME-backed specification based on a subset of the AppStream meta-data proposal. An AppData file comes down to an XML file that specifies the basic program information like the license, name, and descriptions of the program. Screenshots of the program can also be specified via URLs. The AppData specification can be found on this web page.
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