Yes, the location can be tracked for Clock-Ins and for the Check-Ins using the PK4 TimeTracker application.

There is an alert message on the device when you log in to the PK4 TimeTracker application as "Allow Time Tracker app to track your Location, Deny, Allow". Click the Allow button and the PK4 TimeTracker application starts tracking the location for Clock-In/Out and Check-In/Out.

The location details are saved and shown in Salesforce in the Time Details tab as in the screenshot below.

Note: The location tracking should be enabled in the PK4 TimeTracker configuration screen in Salesforce only then you see the message as 

"Allow Time Tracker app to track your Location" when you log into the PK4 TimeTracker application on the device.