Thank you, I already solved my problem.
I attached a Javascript namespace to WebView and put onclick="NameSpace.CallSub('FunctionName', true, 'Parameters');"
Hope this help anyone trying to communicate javascript with Basic 4 Android functions.
However, I've another doubt, what is the best solution to download audio files from remote server to my app? I tried to base64 encode it via XML and the parse it in my app but I got out of memory messages.