You can measure time, take intermediate times, or take lap times using the stopwatch.
and from the following:
Split timing — to take intermediate times. To reset the time without saving it, select
Lap timing — to take lap times
Continue — to view the timing that you have set in the background. To set the
stopwatch timing in the background, press the end key.
Show last — to view the most recently measured time if the stopwatch is not reset
View times or Delete times — to view or delete the saved times
To set the stopwatch timing in the background, press the end key.