I turn it off after my foam rolling and stretching.
I tend to keep it on so I can keep tabs on how fast my HR falls back to normal. Its fun to see it fall faster as I get more fit.
I usually end my session after my cool down. That stops the clock and calorie count.
But I often leave it on just watching my heart rate drop for a bit longer. It's nice to see how quickly it goes to normal.
The side effects of allergy medications keep some people from using them. Natural remedies can be a great alternative, but some are more effective than others.