Yaaic is free and will remain free!
If you like Yaaic and as developing the client is very time-consuming, you can support me by donating a small amount.
If you don't like paypal or if you are sitting on a pile of android devices and you don't know where to store them, let me know ;)
I love seeing yaaic being used all around the globe. Just send me a postcard from where you live and make me happy! :)
If you are a Java/Android developer, you can also contribute to yaaic by coding. :)
Just take a look at the developer page.