The issue with the EL PAÍS app not opening on iOS 15.8.4 is a known problem that has affected many users. According to EL PAÍS, a technical error in a previous version of their iOS app caused it to crash or fail to launch for some users. This was resolved in a newer version of the app now available on the App Store. If you're still experiencing this issue, it's likely because you have the outdated, problematic version installed on your device1.

Recommended steps to resolve the issue:
- Delete the EL PAÍS app from your iPhone.
- Reinstall the latest version from the App Store, which should address the compatibility and crashing problems14.
- Update All Apps: Open the App Store, tap your profile icon, and install all available updates to ensure all your apps are compatible with iOS 15.8.42.

Additional troubleshooting (if the problem persists):
- Restart your iPhone after reinstalling the app6.
- Check for Screen Time restrictions that might block app access. Go to Settings > Screen Time and verify no restrictions are set for the EL PAÍS app2.
- Force close and reopen the EL PAÍS app if it becomes unresponsive64.

Note that some apps, after iOS updates, may require additional updates to maintain compatibility. Regularly updating your apps is important to prevent such issues2. If you've followed all these steps and the app still won't open, it may be due to limitations of iOS 15.8.4 or unresolved app-side bugs. In such cases, contacting EL PAÍS support ([email protected]) may help7.