Location history can be viewed for anyone you are paired with and tracking, by going to the list of people on the home screen, tapping their name in the list, then tapping any of the bottom tab bar history indicators.
If the person you have selected has not been online during that time period, it will only show their last location. You can tap "Report" to select a date range, if you know when they last were online.
" shows you where someone is now, if they are tracking out using Chirp GPS app
"Today" shows you all of the points they have been at on today's date
"24 Hrs" shows you the last 24 hours
"48 Hrs" shows you the last 48 hours
"Reports" gives you the ability to select a date range, and show a heat map, or all location recorded.
If you want to see your own location history, just tap "Me" on the 3 tab menu just under the map.