Tokyo startup Genkii has released a new text communication app for the iPhone and iPod Touch, called Sparkle IM that allows messaging with Second Life (and opensim style) virtual environments. Essentially the application appears to be a lightweight viewer application not unlike SLeek (currently on hold, development-wise), AjaxLife, and similar, in that it essentially logs your avatar in, and gives you a non-graphical interface to communicate with others.
Genkii are also working on a lightweight graphical 3D environment for the iPhone, also part of the Sparkle umbrella brand, called (rather simply) Sparkle 3D, that may in future be integrated with other virtual environments.
Sparkle IM is priced variously, depending on where you are, but at about 4-5 dollars (for the special, introductory price) might be a little expensive compared to many of your existing apps.
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