What I have done with mine: I can set the HRM to track my HR and beep if I am not within my goal HR (based on age-- My HRM calculates it, but 220-your age= Max HR: 60% of Max is your lower limit and 85% of Max is your upper limit). So I set it to beep when I am too high or too low, but I use the notes section at the bottom of my fitness tracker to input the data from my workout: Total Time, Avg HR, and Max HR.
What I log in my tracker is my normal exercise routines-- the HRM just lets me know when I am not working hard enough and I need to step it up.
I also love that when I am doing gym cardio, the machines pick up the signal from my HRM constantly, so I do not have to remember to use the HR handles to check.