An app is a package of executable code and other resources; an app package includes a manifest that lists all package components. App packages are encrypted in the following contexts:
Apps can span multiple packages, which is how Xbox One supports downloadable content and cross-title sharing. Packages can specify static resources that must be present and loaded for the app to run. These packages can also specify dynamic resources that are loaded on demand, and even resources that can be downloaded after purchase.
The organization of an app package has several advantages:
Start up time is reduced
Because apps start as soon as the minimum required set of code and resources have been loaded, start up time is reduced. Additional code and resources continue to load in the background.
Order of loading can change dynamically
The order in which app packages are installed can be dynamically changed, so installation can be adjusted to provide the content and features that a user is engaging.
Apps can access downloadable content without a title update
Apps can use dynamic references to access downloadable content that is published after the original app is published, without having to republish the original app. This is in contrast to Xbox 360 titles, for which publishers must distribute a title update to add new downloadable content.
All apps, including those distributed on optical disc, are installed to and run from the hard drive. The Xbox One console includes support for installing and removing apps, so developers do not need to write set-up programs for their apps.
For more information about installing apps, see Streaming Installation and Intelligent Delivery: Overview.