Also Fring Prepare VoIP For The iPhone

Even if in pre-release version, the popular Fring it's ready to land on the iPhone, Fring is a instant messaging software dedicated to mobile phones, smartphones, handheld devices and it support protocols like Skype, MSN Messenger, Google Talk, ICQ, Twitter, Yahoo! and AIM, it allow to make VoIP calls via a SIP provider or using the SkypeOut and SkypeIn service.
Fring works perfectly with WiFi networks (if supported by your device) or by using the Internet connection of your device, the rates for calls over landline phone and cell phones vary depending by your VoIP SIP provider or by SkypeOut fee, if you're using this one.
The download page dedicated to the iPhone show all the necessary instructions to download, install and set up in some easy steps your iPhone with Fring.
However, on the Fring website it's possibile to choose your cellphone brand and model and download the appropriate version.

VoIP On Symbian Phones

Its name is Fring, it's a software still in beta test, to allow owners of phones with Symbian operating system (Nokia at first) with GPRS or Wi-Fi Internet connection to make phone calls by the phone.
The cost is just the one of the GPRS connection or similar of your phone company; So it is possible to call Skype™ users and Google Talk users just paying your cellphone's internet connection and use SkypeOut credit to call regular phones.
If you want to try this software just surf to http://www.fring.com/ or directly to the download page http://www.fring.com/download/, fill the registration module with the requested data: cellphone brand and model, nationality, e-mail address, cellphone number on which Fring will be installed; almost instantly will be sent an SMS to your cellphone containing a link to download and install the software. This link must be "clicked" by the browser of your cellphone, Fring will be downloaded and installed like a normal Symbian application.
After Skype for Pocket PC and Skype for Windows Mobile will Skype release a version for Symbian Phones? Cellphones with this operating system are largely diffused...