You must check in to your meeting when you arrive at the customer's location so that you may begin taking notes for the meeting.
You can log calls from anywhere - you don't have to be at the customer's office to do so.
When you have checked into a meeting (face-to-face or call), you will see the notes page, and you may begin taking notes.
When you are done taking your notes, you may end the meeting by clicking or pressing this button:
Web: END MEETING
Android App: FINISH MEETING