Application Support Directory
Also known as: application support ios, library app support, ios application support directory
The Application Support directory (Library/Application Support) holds an app's persistent support files — databases, configuration, and downloaded resources the app needs to function. Unlike Caches, it is backed up and not purged by the system.
- Located at Library/Application Support; access via FileManager url(for: .applicationSupportDirectory, ...).
- Holds persistent, essential files (databases, config, downloaded assets) and is backed up by default.
- Unlike Library/Caches, the system never auto-purges it — exclude large items from backup with isExcludedFromBackup if needed.
Where it lives and what goes in it
Application Support is the subfolder at Library/Application Support inside the app's container. You get its URL with FileManager.default.url(for: .applicationSupportDirectory, in: .userDomainMask, ...). It is meant for files your app creates and manages that are *essential* to its operation but are not user documents — for example a SQLite/Core Data store, generated indexes, license files, or pre-downloaded assets.
On iOS the folder is not created automatically, so create it with createDirectory(at:withIntermediateDirectories:) before first use. Files here are persistent: the system does not delete them while the app is installed, and they are included in iCloud/iTunes backups by default unless you set the isExcludedFromBackup resource value.
Application Support vs Caches
The key contrast is with Library/Caches. Caches holds *regenerable* data the system may purge under storage pressure and which is never backed up. Application Support holds data that is expensive or impossible to recreate and that should survive across launches and devices. Put your durable database in Application Support; put decoded thumbnails and re-downloadable blobs in Caches.
From a storage-cleaning perspective this matters: data in Caches is safe to clear and the system will already reclaim it, whereas Application Support is real app state that a cleaner should leave alone. Tools like Cleanor target the purgeable, regenerable side of the container rather than persistent support files.