iOS 14.0.1 fixes a bug in third-party apps set as default apps, which used to reset itself after rebooting the iPhone. It also addresses issues with sending email and preventing images from appearing in the News widget. Here are the official release notes from Apple:
This update includes bug fixes for your iPhone.
- Fixes an issue that could cause default browser and mail settings to reset after restarting your iPhone
- Addresses an issue that could prevent camera previews from displaying on iPhone 7 and iPhone 7 Plus
- Fixes an issue that could prevent your iPhone from connecting to Wi-Fi networks
- Resolves an issue that could prevent sending email with some mail providers
- Addresses an issue that could prevent images from appearing in the News widget
- For information on the security content of Apple software updates, please visit this website: https://support.apple.com/kb/HT201222
You can update to iOS 14.0.1 by opening the Settings app, tapping on General and then Software Update.