I have a Fitbit 2. I use it to easily monitor my heart rate. For brain health, I try to do 30 continuous minutes of fast walking/slow jogging to keep my heart rate above 120. I also like to look at my sleep patterns that are recorded by the device. The best use was not planned - it connects wirelessly to my calendar on my Apple iPad and buzzes my wrist to remind me to do things- a useful feature for someone who is in their 60's.