Thank you for sharing this post. It is extremely interesting because I have been seeking to verify the functionality of AASA files under the simulator. However, I have encountered difficulties in consistently ensuring their proper operation, as the simulator frequently malfunctions and requires a complete reload, necessitating the re-initialization of the cache. I primarily rely on an external device to verify the simulator’s functionality.
Additionally, I believe the most recent release is Xcode 26.2, not 26.1, which you are currently using. Please update your Xcode and obtain the new simulators as well.
Since you have already verified that universal links are working properly on real devices, you know is going to work for your customers, the important part on the simulator is find out if the AASA file was registered and if had the time to install and download the file. For that you can use the Tech Note to go over troubleshooting. But as always my recommendation is to verify with a physician device and making sure you are using the latest version of Xcode and that all available simulators are up to date. Sometimes simulator cache can cause unexpected behavior, so clear the simulator data.
Open the Debugging Console while running your app in the simulator and look for logs related to universal links.
You can manually trigger universal link opening from the Notes app I always recommend to see if the applink has been registered. If your app opens correctly, this confirms that universal link handling is set up properly but there might be an issue with how links are being triggered in code. To verify the AASA file in the simulator, make sure the file is accessible without any redirects and is served over HTTPS with a valid TLS certificate. You can try accessing the file directly from the simulator’s Safari browser
xcrun simctl openurl booted https://yourdomain.com/apple-app-site-association
If it returns the expected JSON content, the file is reachable. If not, it could be an issue with domain configuration or caching. Sometimes simulator’s network configuration could cause problems. Disable and re-enable the Wi-Fi in simulator settings or restart the simulator to refresh network settings. Go to in the simulator, toggle Wi-Fi off/on, or reset network settings by going to (This will erase saved Wi-Fi passwords, so make sure you know them beforehand). Since the issue occurs only in simulators, test on different simulator versions (if available) to check if it's a version-specific bug. In the case, please let me know.
Universal Links Tech Note to go over troubleshooting TN3155: Debugging universal links | Apple Developer Documentation
Looking forward to your findings in the simulator.
Albert Pascual
Worldwide Developer Relations.