[one_fourth_last]The app, Timeline Eons Free, presents the entire history of the universe. From the Big Bang to our present 21st-century news. I have really enjoyed looking back on the certain events in the past. I have only experience the free version but there is an $8.99 Timline Eons app out there for purchase. I believe the only difference in the two versions is the ads, but from a teaching standpoint the free version is great.