Cydia is the most popular third party application for iOS devices. You must download  Cydia to install themes, system tweaks, download premium apps for free and install more awesome games and apps.
How to install Cydia for free

Using "Cydia installer" you can download Cydia to your device within few minutes.

Go to  ( cydia website) and download "cydia installer"

Search as on your computer.

Or Know more details about Cydia