To resolve the issue of the American Airlines app displaying a blank screen during login, follow these steps:

1. Force Close the App:
- Double-click the home button or swipe up from the bottom of the screen (if your iPhone does not have a home button) to access the app switcher.
- Swipe left or right to find the American Airlines app.
- Swipe the app up to force close it. Then, reopen the app.

2. Clear App Cache:
- Unfortunately, iOS does not allow direct clearing of an app's cache; however, you can try the next step to effectively refresh it.

3. Reinstall the App:
- Delete the American Airlines app by tapping and holding the app icon until it jiggles, then tap the "X" or select "Remove App" and confirm.
- Go to the App Store, search for "American Airlines," and reinstall it. This can often resolve issues related to corrupted data.

4. Restart Your iPhone:
- Press and hold the power button until the "slide to power off" slider appears, then slide to power off.
- Once your iPhone is off, press and hold the power button again until you see the Apple logo.

5. Check for System Updates:
- Go to Settings > General > Software Update.
- Install any available updates as these can fix bugs that may affect app functionality.

6. Check Network Connection:
- Ensure you have a stable Wi-Fi or cellular data connection. A poor connection can sometimes cause the app not to load properly.

7. Contact Technical Support:
- If none of the above steps work, you can visit the technical support page for American Airlines here for further assistance or to report the issue.

Implementing these steps should help you resolve the login issue with the American Airlines app. For more insights, you can check out discussions about this problem on Reddit here or here. - [learn more]

If the problem persists, it might be related to the app's server status or a broader technical issue, which you can also monitor through American Airlines' official channels. - [learn more]