We were just alerted to a new iPhone and iPod touch app called Ping!, which aims to provide free iPhone-to-iPhone (and iPod touch) messaging to users of those devices. We tried it, and thought it was worthy enough to give a shout out to.

Basically, once you download the free Ping! application, you set up a username, and you are set. You can invite others from within the app over email, letting them know your username, and also set up whether you want push notifications or not. Once you start a conversation, it’s very similar to SMS…except it’s free, and instant. You get the speed of an IM conversation with the persistence of SMS, all at no extra cost. Even better, it works internationally. So you can send and receive messages with people in other countries, and again, at no extra cost.

Go ahead and give Ping! a try, we think you’ll like it.