Regarding built-in iOS apps being split out into the App Store
The idea of Apple unbundling the built-in apps so they can be split out and updated at any time via the App Store is an old one. There are some merits to the idea but also some drawbacks. In theory it would allow for bugs to be fixed and features to be rolled out faster that operating system updates would otherwise allow. In practice, it much more complicated. That's why it's one of those things everyone suggests but few go further than the suggestion. So lets go further.
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