VoIP iPhone Apps
The iPad runs the same OS as the iPhone, so all VoIP Apps developed for the iPhone will work on the iPad. The good news is that you have your choice of VoIP apps developed for the iPhone. Currently there are more than 100 VoIP apps in the iTunes App Store, and the number is growing.
There are few notable iPhone VoIP solutions. Fring was the first VoIP solution to come to the iPhone and it is still one of the best. Fring works by connecting with popular Instant Messenger services such as AIM, Yahoo Messenger, Skype, and Microsoft Live Messenger.
Fring has two positives going for it: It is free and you can use it over 3G data connections. The downside is that the audio quality is not greatyour voice will sound like you are calling from a tin can.
Acrobits soft phone is one of the best VoIP apps you can get. Unlike most VoIP apps, you need to shell out $7.99 for the software, but it is worth it. Acrobits has great audio quality and will tie in with dedicated VoIP services such as Vonage.