Last week, we reported on Apple dropping restrictions on VoIP iPhone applications working over 3G. The change would allow VoIP apps, which previously only worked over Wi-Fi, to make calls using 3G. Popular VoIP apps like iCall and Fring announced 3G support immediately after Apple relaxed the restrictions, but Skype was conspicuously absent from the party.

Today, Skype finally announced plans for a 3G-enabled version of its iPhone application, and it looks to be a fairly significant update. In addition to allowing 3G calls to other Skype users, and SkypeOut calls to actual phone numbers, the new version of the software will also feature an indicator for determining call quality in real time, and “CD quality sound” when calling other Skype users.

The upgraded sound quality comes from the inclusion of Skype’s SILK codec, which was first seen in Skype 4.0 for Windows. According to Skype, the benefits of SILK include:

  • Improving audio bandwidth going from 8 kHz to 12 kHz, meaning that a SILK conversation sounds like you are in the same room as the person you are speaking with
  • Providing real-time bandwidth scalability to deal with degraded network conditions
  • Balancing codec optimization between voice, music and background noise, each of which can have an impact on the overall user experience
  • Delivering a robust solution that delivers a more consistent audio experience, regardless of network conditions and an individual user’s voice signature.

I rely on Skype heavily for podcasting, and I can attest that Skype 4.0’s sound quality was a huge step forward from previous versions. Given the reception variability with 3G connections, SILK should adapt itself very well to the mobile VoIP experience.

There was no mention of video chat capabilities, but I’m hoping that Skype will offer chat on the iPhone sometime this year (Fring already does). Even without dual-cameras, it’s still possible to video chat on the iPhone by shooting yourself with the camera, and talking through the speakerphone. It’s not ideal, but it’s still a better video chat solution than having nothing at all.