In the last few days, my note 8 has rebooted twice. In both cases I was running with it, running strava and Pandora. During the run I hear this horn kind of sound and when I look at my phone, it was rebooting. Any ideas?
Probably not as a preinstalled feature. I'm sure there are some 3rd party apps that can monitor temp, though -- try GSam Battery Monitor or Accubattery.