App thinning in iOS 9: Explained
Over the last year, Apple has introduced new services like iCloud Photo Library and iCloud Music Library that keep recent and frequently accessed data on the device but offload older and infrequently accessed data to Apple's servers. That nearline strategy helps ensure more space is available for updates to begin with. With iOS 9, Apple is taking space-savings to a whole new level with App thinning, which includes asset slicing, on-demand resources, and bitcode.
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