Arc collects location and activity data from your phone and stores is securely on your phone and in your private iCloud account.
This data is processed locally on your phone, and is presented in the app to give you insights into your daily activities.
The data is backed up to your secure private iCloud account, which is only accessible by you.
Arc is designed with the intent that access to your data is only possible via your personal iCloud account.
None of your data is shared with third parties, for any purpose.