No. All of your events and reminders are synced from your calendar services (such as iCloud, Google, or Exchange) and stored on your device. Your personal data is never sent to Flexibits or anyone else.
Fantastical uses your username and password to sync and display your events and reminders. Your username and password are stored securely on your Mac in the Keychain. The Keychain is part of macOS and is responsible for securely storing usernames and passwords. Your account information is never used for any reason other than to sync your data, and your account information never leaves your computer.
Fantastical for Mac:
Fantastical for iPhone and Fantastical for iPad:
Please contact us and we'll get back to you.