In Ticket History, you will be able to view:
Initial report date
Comments
Updates to a Ticket's progress
Updates to a Ticket's priority
A Ticket Due Date being changed
Who is adding/removing Followers
Web
1) While in Tickets, find and click on the Ticket you wish to view.
2) In the body of your Ticket, scroll down. You will find the Ticket History located at the bottom!
Mobile App
1) While in Tickets, tap on the Ticket you want to view the History of.
2) Scroll to the bottom of the Ticket to find the History!