Apple iPhone users may soon be able to make calls without using cell phone minutes as Global IP Solutions announced Monday a software developer's kit that enables voice over Internet Protocol on Apple's handset.
Developers will be able to use VoiceEngine Mobile to build standalone VoIP applications for Apple's App Store, as well as applications that integrate real-time VoIP communication into iPhone games, chats, social networking, and more.

Instant-messaging chat or dissing your Texas Hold 'em opponents on the iPhone just got one step closer. Global IP Solutions (GIPS) has announced the release of its near-ubiquitous voice-over IP (VoIP) developer software for the iPhone engineering crowd. GIPS VoiceEngine Mobile is a development toolkit for iPhone software developers who want to add voice and streaming video to iPhone applications.

"The popularity of the iPhone, along with the emergence of various applications and faster connectivity, makes it an ideal platform for developing application that incorporate quality real-time VoIP, giving consumers real-world communication experiences like in-game, multi-person chat," said Emerick Woods, Global IP Solutions' CEO, in a statement.

Users hoping to utilize the iPhone 3G's high-speed network for VoIP calls are out of luck, as the VoiceEngine Mobile will only work on Wi-Fi hotspots. This is due to Apple's agreement with its exclusive U.S. carrier AT&T (NYSE: T) to remove applications that violate the mobile operator's terms of services. VoIP calls on a 3G network could potentially eat into AT&T's voice revenues.

Customers who now enjoy the voice features of Facebook and MySpace may soon be able to communicate in the same way when accessing the sites on their iPhones -- once a motivated software developer creates the app for iPhone customers. Similar applications that bring voice to instant-messenger software running on the iPhone will also be possible. Also of interest is the possibility that using stable VoIP software on the iPhone would allow users to bypass the AT&T voice network entirely -- all that is required would be a VoIP engine and interface. Users could make calls directly over the Wi-Fi network and avoid the tollgate of a cellular provider.

Apple acknowledged that it would allow Wi-Fi VoIP, but not over other networks, as that would violate its exclusivity contract with AT&T. Numerous blogs already detail ways in which users can enable Skype applications, for example, to place and receive phone calls over Wi-Fi and "off the cell network."

Sources revealed that a number of vendors are already using the SDK to develop iPhone applications, but refused to give names. (Steve Jobs announced today that the iPhone application store sold $30 million in apps this month alone.)

Without a VoIP engine, software engineers would have to solve myriad voice and video issues, such as long latency times, jittery quality and loss of voice packets. Couple that with the bandwidth constraints of delivering streaming applications over Wi-Fi, and engineers could nearly double their product-development cycle. Releasing the GIPS voice engine for the iPhone operating system and programming environment brings applications to market faster.

Rust declined to provide pricing, saying only, "The software is priced on a sliding scale for developers, plus a royalty fee for each application sold."