indicator-application-gtk2 software package provides Application Indicators, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install indicator-application-gtk2
indicator-application-gtk2 is installed in your system.
Make ensure the indicator-application-gtk2 package were installed using the commands given below,
$ sudo dpkg-query -l | grep indicator-application-gtk2 *
You will get with indicator-application-gtk2 package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | GNOME |
| Package | indicator-application-gtk2 |
| Version | 12.10.0.1-0ubuntu2 |
| Description | Application Indicators |
| Sub Section | GNOME |