While BlackBerry owners have the luxury of using BlackBerry Messenger to communicate with each other for free, only they can use this convenient app. Thanks to an agreement with Canadian and U.S. carriers, Kik Chat allows you to send and receive text messages from other Kik users or mobile numbers for free. The app uses actual mobile numbers to send and receive messages instead of e-mail-to-SMS gateways, which can cause messaging delays. The only catch is that if you're sending to mobile numbers, you're limited to 100 outgoing messages each month (there is no paid version that allows unlimited outgoing messages). Incoming messages are unlimited, as are Kik-to-Kik messages.
After downloading Kik Chat from BlackBerry App World, the app will ask you to enter your name and mobile number so it can send a text message confirmation for registration. Once it verifies your device, you can start sending messages to your contacts. It works strictly as a text messaging application: you must select a contact or create a new one if you're sending an SMS to a new phone number. Messages are threaded and separated by contacts to make reading and responding simple. You can manage sound and vibration preferences under the Available and Unavailable profile settings within the app. From here, you can also view your phone number, how your name appears to others, and how many outgoing message credits you have left.
If you don't send out too many text messages, you may want to consider cancelling your texting package and picking up Kik Chat for BlackBerry (also available for the iPhone).
Want to read about more apps that dash your text messaging costs? Check out Text Message for Free: Apps for Android, BlackBerry, and iPhone OS.