A. 1. Update iOS: Ensure your device is running the latest version of iOS. Go to 'Settings' > 'General' > 'Software Update' to check for updates. 2. Clear app cache: Go to 'Settings' > 'General' > 'iPhone Storage', find WienMobil, and select 'Offload App' to clear cache without deleting data.

B. 3. Reinstall the app: If crashes continue, delete the app and reinstall it from the App Store.