A. 1. Ensure your iPhone is running the latest version of iOS. Go to Settings > General > Software Update and install any available updates. 2. Update the GHIN app to the latest version. Open the App Store, tap on your profile icon, scroll down to see pending updates, and update GHIN if necessary. 3. Clear the app's cache by deleting and reinstalling the app. Press and hold the GHIN app icon until it wiggles, tap the 'X' to delete it, then reinstall it from the App Store.

B. 4. Restart your iPhone to clear temporary files that may be causing the app to crash. Press and hold the power button until you see the slider, then slide to power off. Turn it back on after a few seconds.