snip.js

button.addEventListener('click', function(e) {
    if (tmpFile) {
        var intent = Ti.Android.createIntent({
            action: Ti.Android.ACTION_VIEW,
            type: "application/pdf",
            data: tmpFile.nativePath
        });

        try {
            Ti.Android.currentActivity.startActivity(intent);
        } catch(e) {
            Ti.API.debug(e);
            alert('No apps PDF apps installed!');
        }
    }
});