Yahoo recently made a stand-alone version of its Messenger instant messaging application available for the iPhone. How does it compare?I admit that I rarely use IM from my phone, but it has come in handy on occasion. Since AOL's AIM app became available for the iPhone last summer, I've used it from time to time, and it generally works well for short conversations.

Yahoo has finally gotten around to offering a version of its own messaging client for the iPhone. Yahoo IM is built into the new Yahoo Mobile application that was recently made available for the iPhone. If you're not interested in installing the larger program, Yahoo Messenger for the iPhone can cover the basics of IM.

The app is a free download from the iPhone Apps Store. It downloaded and installed in a snap via 3G. Signing in and connecting, however, were a bit problematic.

I launched the app, entered my username and password, and watched it chug along "connecting" for more than five minutes. Eventually it logged in. After that first time, it logged in faster on subsequent attempts.

The user interface is as easy to figure out as any other on the iPhone. There are three tabs along the bottom that give you access to your contacts, messages and settings. Tapping any of your contacts brings up a screen in which to compose IMs. There is a rich set of emoticons that can be inserted into each message, and you can also insert URLs and images.

Composing and sending messages is a snap. What's sort of interesting is that in the main message screen, the blank spot to compose a message has a note that says "What are you doing?" If that sounds familiar, think Twitter. You can also start typing new messages from this screen, and inserting a recipient is as simple as pressing the screen.

The settings let you control your availability (available, unavailable, invisible), as well as customize how you view your contacts.

In all, it's a good IM client for the iPhone, and is well deserving of the four stars it is currently rated at in the iPhone Apps Store.

If you're more fully entwined in Yahoo's services, you'd probably be better off just using the Yahoo Mobile application, which includes tons of other services and features.