It will stay on the phone, but won’t be available for downloading again since it’s being removed by Apple. Once the phone dies and the user buys a new phone, there won’t be a way to get this app unless the user copied the app package through a third party application on a Mac (Apple removed the ability to sync/backup app packages to a Mac since iTunes 12.7).

It so happened once that iPhone removed an app that I didn't use for some time to save space on the phone, leaving behind just an icon shortcut. When I tried to use it, it tried to download it back, but couldn't, because the app had been removed from the store.

So by default you can't count on your apps staying on the phone.

> Once the phone dies and the user buys a new phone, there won’t be a way to get this app unless the user copied the app package through a third party application on a Mac (Apple removed the ability to sync/backup app packages to a Mac since iTunes 12.7).

yeah. thats where the experience diverges from other platforms.

the current device, with the current OS, won't have any problems. asking for more is mostly a different standard than other platforms, sad to hear they killed making your own app package copies.

Don't iOS apps check in with Apple periodically for permission to run?

A future OS update can break app compatibility if the app is not updated, apps not on the store won't be updated

Restoring a device from cloud backup will download all your apps, except apps no longer on the store

The device right now, with the OS right now, with the app right now will still be able to use this app and its file sharing feature in perpetuity which is an aspect that isn't different or worse than other kinds of devices or computers. Only the system restore embellishments being different or better or worse. People on other systems that pay for apps can still run into scenarios where their updated operating system is not compatible with an app they paid for. I'm not trying to be an apologist for things Apple or the mobile landscape could do better, only pointing out the standard people seem to be asking for without realizing it.

My understanding is that if the developer certificate is revoked, then the app would fail to run. But otherwise, apps on the device should run even if they’re removed from the App Store (by Apple or by the developer).