var sep = Titanium.Filesystem.getSeparator();
var zip = Titanium.Filesystem.getFile(Titanium.Filesystem.resourcesDirectory, "db.zip");
if (zip && zip != undefined) {
    Titanium.API.info("zip file found");
}
else {
    Titanium.API.info("zip file not found");
}
var dest = Titanium.Filesystem.getFile(Titanium.Filesystem.applicationDataDirectory);
if (dest && dest != undefined) {
    Titanium.API.info("dest folder: " + dest + "found");
}
else {
    Titanium.API.info("dest folder " + dest + " not found");
}

Titanium.Codec.extractZip(root, dest, function(dest) {
    alert("Extracted zip file to: " + dest);
});

var db = Ti.Database.install(Titanium.Filesystem.applicationDataDirectory + sep + 'airroutes.mp3', 'airroutes');