Recent history shows up in the files and folders lens in the Unity Launcher. To delete
the recent history, open the terminal and type:
sudo rm ~/.local/share/zeitgeist/activity.sqlite
sudo zeitgeist-daemon –replace
After that close terminal, log out and log in again.
Alternatively, you can install activity log manager, as detailed below:
sudo add-apt-repository ppa:zeitgeist/ppa
sudo apt-get update
sudo apt-get upgrade
zeitgeist-daemon –replace
sudo apt-get install activity-log-manager
Then look for the application in the applications lens.