I am able to post to Google Place Actions from android using the below code to post a place as in here (partly based on this answer by kuester2000).
 public void postMyPlaces(final double lat, final double lng, String name){
    Log.i(TAG," postMyPlaces called");
    
    Thread t = new Thread(){
        
        @Override
        public void run() {
            super.run();
            
            String url = "https://maps.googleapis.com/maps/api/place/add/json?sensor=true&key=" +GOOGLE_API_KEY ;
            
            
            HttpParams httpParameters = new BasicHttpParams();
            // Set the timeout in milliseconds until a connection is established.
            // The default value is zero, that means the timeout is not used. 
            int timeoutConnection = 3000;
            HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
            // Set the default socket timeout (SO_TIMEOUT) 
            // in milliseconds which is the timeout for waiting for data.
            int timeoutSocket = 5000;
            HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);
            DefaultHttpClient httpClient = new DefaultHttpClient(httpParameters);
            
            HttpPost httpPost = new HttpPost(url);
            Log.i(TAG," postMyPlaces called "+ url);
            httpPost.setHeader("Content-type", "application/json");
        
            
            //Create a json request object to send it via HTTPS
            LocationModel uLocation = new LocationModel(Double.toString(lat),Double.toString(lng));
            MyPlacesModelImpl myPlacesPayload = new MyPlacesModelImpl("50","My Car","parking","en-AU",uLocation);
            
            
            StringEntity entity = null;
            try {
                entity = new StringEntity(myPlacesPayload.toJSON().toString());
            } catch (UnsupportedEncodingException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            
            httpPost.setEntity(entity);
            HttpResponse httpResponse = null;
            try {
                 httpResponse = httpClient.execute(httpPost);
                String resp = httpResponse.toString();
                Log.i(TAG,resp);
            } catch (ClientProtocolException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            
        };
        
    };
    t.start();
    
    
}
I am getting the response as "OK". But how to see these places which I have added in map???? Please help
 
     
    