Is there a way to wake up an application that is completely turned off in iOS using a server push notification or scheduler and collect whether the user is using the smartphone and record it locally or send it to the server(in the background)? It would be nice use Flutter, but it's okay if don't.
They say it's impossible on iOS, so I'm contemplating how to do it.
You should be able to do this using background notifications, however the user can disallow you to do so. So there is no 100% certainty this will succeed.
On top of that, the time for the background handling is limited and decided by the OS; top of my mind I believe it is up to 10s, but I could be mistaken here. If there is no network call it could also fail for that reason. I would in such case register locally what you need to register and send it shortly after app launch for instance.
Please have a look at Apple's Push Notification documentation: https://developer.apple.com/documentation/usernotifications/setting_up_a_remote_notification_server/pushing_background_updates_to_your_app
