When concurrent editing, sometimes it is useful to follow a user as he/she edits the code. To do this, simply click on the user name and it should turn bold. Your view will now automatically scroll to always keep this person's cursor within the view. If you are both writing code together, you may want to use this along with the split view.
Below is a screenshot where the right side is currently being followed and the left side is being edited. Two people are editing jam/Jolly. Jam Jenkins is editing on line 10 and the other person (let's call her Ann) is editing on line 41. The left side always scrolls to keep Ann's cursor visible. The right side always scrolls to keep Jam's cursor visible. This way Ann and Jam can collaborate and both know what each other is editing. Notice that the 'Jam Jenkins' label on the right screen is bold, but the one on the left is not. This is because the one on the right (the bold one) is currently being followed by Ann. Notice that the 'Jam Jenkins' label on the left is all the way to the top. This is because in the left view, the cursor is entirely off screen above the current location.
To stop following a user, just click on the name again and it will go back to the normal font (not bold any more).