Proper way of checking for Reachability and App Store submission tips

Question

I have read in the App Store Submission Tips that

If your application provides functionality that requires access to a network, it's very important that your code include a customer alert or notification when the network is not available.

In fact, there are two entries in that submission tips list concerning Reachability (Don't Forget to Include Network Error Alerts in Your Code and Be Sure to Provide Network Error Messages). But I don´t know how an app is expected to manage Reachability actually:

1) Should you listen for network reachability status changes, and notify the user every time the network is not available? Or should you check for the reachability of the network when you are about to perform a network operation, and then notify if needed? Or both?

2) Is it required to check for the reachability of the certain remote hosts you need to call in your network operations, or checking for network availability (either WiFi or WWAN) will be enough?

I'd appreciate some guidance from someone who had already successfully submitted an app to the App Store.

Thanks in advance

Answer 1

1) If your app only needs to access the network when the user specifically chooses to do something, then checking at that time is fine. Depending on your app, you might want to listen for changes in reachability and update your UI based on the current status (such as disable a button if there is no network connection). Don't pop alerts every time the reachability status changes. That would be annoying.

2) Depends on your needs. If you have something that always connects to a specific host then checking that host would be good. If the access can be to anything on the Internet then simply check for Internet access.

All of this can be done with the Reachability class from the "Reachability" sample app.