One of the best chat applications is clearly Yahoo Messenger. The computer version of this program is easy to use and the mobile version lives up to this standard so to speak. It is easy to use and allows you to do everything on your smart phone that you can do on your desktop. If, for some odd reason, you do not have such an app installed on your smart phone, or if there is some problem with it, you can send and receive chat messages via text message. If you are doing this and want to continue with it when you are driving, you will want . This app allows you to listen to text messages as audio and you can customize the auto responder that comes with the app to let your contacts know that you are not ignoring them but are just driving at the moment.