If you are using a mobile device, then the best thing that you can do is to install a Kannada keyboard. You will not only type in Kannada but also will be able to send and receive text messages in this language. The best thing is that you can do this without having to pay for an app that costs money. 

So, if you want to type in Kannada, the best thing that you can do is to install this keyboard. You will not need to pay for an app and you will not need to install a new keyboard.