Steve Jobs' green light for third party apps for the iPhone--including WiFi based VoIP--is expected to see several voice widgets quickly come to market. U.K. provider Truphone had already released a demonstration model late last year. Over the weekend, they issued a careful statement acknowledging their interest and indicating they would be developing a fully fledged application. DSL Reports also wrote that video chat developer SightSpeed was working on a VoIP app, but that iPhone's camera placement was proving problematic.  

The big question is what Skype is up to. The sheer popularity of the iPhone--and the chance to share in the $100 million developer fund Apple and its VC partners have put on the table--makes it an almost certainty Skype will move quickly to be part of the play. Certainly that is what the expectation is from the analysts [1] who closely watch Skype. The combination of iPhone and Skype would definitely make the cellular industry worried--if they are not already. But while some see Apple's VoIP announcement as a game changer, [2] others such as ZNet's Russell Shaw [3] cautions that Vonage offered VoIP over WiFi and dropped it. True, but that was pre-iPhone and we have already seen enough evidence to suggest the iPhone is the breakthrough product [4] for the internet moving to the wireless space.

For more:
- Apple iPhone SDK and developer fund Release [5]
- SightSpeed works on iPhone VoIP app Article [6]
- VoIP on iPhone a possibility Article [7]
- Truphone a starter for iPhone VoIP Blog [8]

Related articles:
Vodafone swings behind mobile VoIP Article [9] 
T-Mobile offers $10-a-month calling Article [10]
FierceWireless is sponsoring The Path to 4G seminar [11]at next month's CTIA trade-show