How to view open and closed activities of a contact?
To view activities related to a contact
1. Open the Bigin app on your iPhone.
2. Navigate to the Contacts 
module.
3. Select the desired contact record.
4. Switch to the Related tab.
The contact's list of open activities can be found under Open Activities, and the list of closed activities can be found under Closed Activities.
Note: You may also choose to add a new task, event, or call by simply tapping the Add 
icon at the top right of the screen and selecting the relevant option from the dropdown.