Your entries
Happiness is designed for personal reflection. Unless a feature clearly says it syncs or shares data, treat entries as local app content connected to your device and Apple account settings.
Backups
iCloud backup and device transfer behavior are controlled by Apple and your device settings. Keep separate records for anything you cannot afford to lose.
Support emails
When you contact support, only send screenshots or journal text you are comfortable sharing. Support messages are used to answer your question.
Read the full Privacy Policy for legal details.