Every software center that exists allows the user to look at screenshots and a long description of the application before it is installed. For most users it allows them to answer the question Do I want to install this application? Traditionally in Linux distributions, we have none of this data for the vast majority of our desktop user-installable applications. To solve this, we have defined a new data file, which the upstream project can optionally translate using the same technique as GSetting schemas or Desktop files. Rather than create a new schema from scratch, we'll be using a subset of the AppStream metadata proposal.