Hey there, let's unpack this confusing issue you're facing with your standalone Apple Watch app. The behavior you're seeing is actually tied to WatchOS's network routing policies when paired with an iPhone, even for apps designed to run independently. Here's a breakdown:

Key Reasons for the Scenario 3 Failure #

1. Paired iPhone Network Dependency for Third-Party Apps
   When your Apple Watch is paired with an iPhone, WatchOS often prioritizes routing third-party app network traffic through the iPhone—even if the watch is connected to its own WiFi. In your scenario 3 (iPhone WiFi off, watch WiFi on), the watch is still trying to send your app's API requests through the offline iPhone, leading to the -1009 "Internet appears offline" error. This is a system-level restriction, not an issue with your code.

2. System-Level Apps (Like Siri) Have Special Network Access
   Siri is a first-party, system-level service on WatchOS, so it bypasses this third-party routing limitation. It can directly use the watch's WiFi connection to communicate with Apple's servers, which is why it works even when the iPhone is offline. This same exception applies to other Apple-built services, but not to third-party standalone apps.

3. App Store Behavior Confirms System-Level Restriction
   The fact that the Apple Watch App Store exhibits the same behavior reinforces this: third-party apps (and even the App Store itself, in this context) are bound by the paired iPhone's network routing rules.

Steps to Verify & Mitigate #

• Test with Unpaired Watch: Try unpairing your Apple Watch from the iPhone, connect it to WiFi, and run your app. If the API requests work, this confirms the paired routing limitation is the root cause.
• Reset Watch Network Settings: Go to Watch Settings > General > Reset > Reset Network Settings on your Apple Watch. This can resolve any cached network configuration issues that might be exacerbating the problem.
• Check WiFi Connection Validity: Ensure your watch's WiFi is actually connected to a working internet network (you can verify this in Watch Settings > WiFi by checking the connected network's details and confirming it has a valid IP address).

Why Scenarios 1, 2, 4 Behave as Expected #

• Scenario 1 (Both WiFi on): The watch can use either its own WiFi or the iPhone's network for requests, so everything works.
• Scenario 2 (iPhone WiFi on, watch WiFi off): The watch uses Bluetooth to share the iPhone's WiFi connection, hence successful requests.
• Scenario 4 (Both WiFi off): No active network connection exists for either device, so failure is expected.

内容的提问来源于stack exchange，提问作者SVG