The is reporting that eBay's Skype unit will release a version of its voice-over-IP Internet phone software for the iPhone on 31-Mar-09. The software, which also works on the second-generation iPod touch when outfitted with a microphone, will enable users to call other Skype users on computers or other mobile phones for free. Skype users can also call normal phones for a fee, typically 2.1 cents per minute within the United States and many other countries. , but are lower than those charged by phone companies.
[Update: The application is via the iTunes Store.]
Apple limits VoIP apps to working over Wi-Fi, preventing VoIP calls from being made while the phone is using the 3G cellular data network. This is likely an effort to reduce excessive usage of the unlimited data plan associated with the iPhone in at least the United States, and to prevent users from avoiding the lucrative - - cellular calling rates enjoyed by the carriers. (Don't get us started on the insane rates charged for SMS messages, which are at least  as communicating with the Hubble Space Telescope!)
Apple said in the recent iPhone 3.0 software announcement that it would be adding VoIP-related APIs to the iPhone 3.0 software (see "," 2009-03-17). It's not yet known what enhancements will become possible with these new APIs, but it's good to see that Apple is at least paying some attention to the burgeoning VoIP market.
The entrance of Skype into the iPhone world is a big deal. Skype claims 405 million users around the world, and many people now conduct much of their voice communications via Skype. In addition to the Mac and Windows software, Skype offers versions of its software for Windows Mobile-based smartphones, for the Android G1, and for the Nokia Internet Tablets. Versions for the BlackBerry and are slated to appear later this year.
Interestingly, although other VoIP software that enables free calls to Skype members, such as and , is currently available for the iPhone, we haven't noticed it gaining significant traction among Skype users. According to the , other software that works with Skype doesn't offer all of the service's features.
Bernard Lunn on ReadWriteWeb has an than it gets. In short, Skype has become a mainstream company that's not running on the fumes of venture capital funding, has turned a real profit, and is growing fast due in part to the economic downturn.
We now use Skype for all of our staff calls, and it has also become the standard for podcast interview recording in our circles. Although Skype is far from perfect, our experience is that it both is more reliable and offers higher audio quality than iChat. And while Skype's reliability is much worse than normal phone calls, the quality is often better, due to higher bandwidth, sophisticated codecs, and better equipment. Landline calls are limited to 56 Kbps of bandwidth, whereas Skype could use much more, though it apparently most of the time. And most normal phone microphones and speakers can't compete with even an inexpensive USB headset, much less a high-quality headset like the  that I use.
I'll be interested to test the Skype iPhone app against Skype on my Mac, and against Truphone and Fring, to see how it all compares.