There was a time when Blackberry users rubbed their Blackberry Messenger service in all of our faces, and rightfully so. Having a free means of contacting their friends, with nothing more than a pin number to send messages and avoid SMS charges from their carrier was something only they could enjoy. iPhone app developers caught up with the game with applications like WhatsApp and took it even one step further providing a Blackberry and Android version, but it wasn’t long before they became paid apps.

PingChat! now offers a completely free cross-platform mobile chat program that supports iPhone, Blackberry and Android handsets. The app is downloadable directly from their website, which means that Blackberry users who don’t have access to the Blackberry App World can still download and use PingChat!

Once you’ve downloaded PingChat! to your phone you will be required to register the app. All that means is you will be asked to enter a unique username, which is linked to your phone number.

In order to chat with your friends using PingChat!, you have to have their username. They do make it easy to get the word out there, giving you a quick and easy way to broadcast your username on Facebook, Twitter or via email. As you start to add contacts and receive messages, you can easily link your PingChat! contacts to your address book.

Once you’re all set up, you can start sending and receiving messages. But you’re not just limited to text. You can send picture messages, by taking a photo while the app is open or by choosing a photo saved on your phone. You can record a voice note up to 30 seconds long. Using PingChat!, you can also send videos saved or recorded on your phone to your friends. iPhone 3G users can send videos that have been recorded with other third party apps that have been saved to the camera roll. Blackberry, Android and iPhone 3GS/4 users can send videos recorded with their native video camera apps. You can also send the contact details of anyone in your address book.

And it doesn’t end there. You can send your exact location using Google Maps, a feature that would be of huge help if you’re lost or your car has broken down and need someone to pick you up. Your location will be uploaded to PingChat! as a map.

And of course, PingChat! uses push notifications to let you know when you have a new message. You can choose to toggle the sound and vibration for notifications on and off from directly within the app’s settings on the iPhone. And if you change your number or phone, you can unregister the account, and re-register with so that you don’t have to change your username.

The Blackberry settings are limited to unregistering your account and choosing which sound profile to use with the app. iPhone users will be happy to know that their version supports landscape mode. The app works over 3G, EDGE and WiFi so you can keep in touch with your friends no matter where you are.

Have you used PingChat? Let us know what you think of it in the comments.