A previous beta version, which required a jailbroken iPhone to work, proved extremely popular. Now anyone can get hold of the app that allows them to instant message their contacts on Skype, MSN, Google Talk, ICQ, Twitter, Yahoo! and AIM, as well as make cheap calls via a Wi-Fi connection.
Finally, it’s possible to keep in contact with everyone when away from the desktop environment, and all from the single application.
Unfortunately, Apple’s rules mean that the service can’t run in the background, so you have to keep it open if you want to maintain a conversation. However, it does save current sessions when inactive. At some point, Apple is supposed to be introducing a “push” service for third-party applications that will allow them to notify the user when certain events have occurred. Until then, the app is slightly stunted, but still useful.
Here’s an interesting intro video about the app:
Available now. [iTunes link]