During a question and answer session following the iPhone Software Roadmap event in early March, a press member asked about the possibility of a VoIP (voice-over-IP) application for the iPhone. Steve Jobs left the door wide open, saying that while Apple wouldn't allow such an application to access the cellular network, VoIP is certainly a possibility over WiFi.
JAJAH has announced plans to capitalize on this opportunity by offering a native iPhone application built with Apple's SDK this Summer. The app will work as a full VoIP client when connected to WiFi networks, and use a callback methodology (in which the user calls a designated local number and is then called back and connected to the desired phone number) when using a cellular network. The company has long offered a Web-based VoIP offering for the iPhone.