...but I have doubts you can avoid protocol, especally with such frequent polling, if this app is meant for the store.
Now ideally we would want to create a service that can run in background (indefinitely), poll the ip Address of the device every 10 seconds, and if it sees that the ip has changed, then call a web service notifying the server about the same.
You are not going to be able to meet these requirements. iOS does not allow apps to resume in the background every 10 seconds. That’s not an arbitrary restriction; such an execution pattern would seriously compromise the device’s standby battery life. You will need to rethink how your app and server interact to track clients.
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Apple Developer Relations, Developer Technical Support, Core OS/Hardware
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