Fring, which is a service that enables you to use communicate with friends over multiple instant messaging clients, now works on the iPhone over a 3G network.

Fring has been available on the iPhone for a long time; however it previously only worked with WiFi connectivity.  The 3G support that’s been added enables users to make free voice and video calls using their favourite instant messaging client, such as Skype, Googletalk and MSN.

Fring can combine all your contacts from various clients into one manageable list, so Skype, MSN contracts can all be talked to without needed to switch between programs. Additionally, you can also use LastFM to listen to music and to see what your friends have been viewing.

Fring also enables users to benefit from local and international calls.

You can download fring for free for your iPhone by clicking here.