Q:

Asynchronous HTTP post with JSON parsing the result with Android 4? 

I'm quite new to Android.  I've been looking for a good example on how to perform a HTTP post request over the web, but I'm hesitating on which to use since I'm only developing for Android 4.  I want something asynchronous, fast and simple.  An example with JSON result parsing would be much appreciated.  Any ideas?  Should I use Apache HTTP Client or HttpURLConnection? 

A:

For me RestTemplate is one of the easiest ways to consume REST services on Android. 
Example for JSON:
RestTemplate template = new RestTemplate();
        HttpComponentsClientHttpRequestFactory requestFactory = new HttpComponentsClientHttpRequestFactory();

    //setting timeout
    requestFactory.getHttpClient().getParams().setIntParameter(CoreConnectionPNames. CONNECTION_TIMEOUT,
            HTTP_TIMEOUT);
    requestFactory.getHttpClient().getParams().setIntParameter(CoreConnectionPNames. SO_TIMEOUT,
            HTTP_TIMEOUT);

    template.setRequestFactory(requestFactory);

    //setting converter for JSON
    List<HttpMessageConverter<? >> converters = template.getMessageConverters();
    converters.add(new MappingJacksonHttpMessageConverter());
    template.setMessageConverters(converters);

    ResponseEntity<ResponseObject> response = template.postForEntity(URL, requestObject, ResponseObject.class);

    ResponseObject result = response.getBody();

To make this works You need RestTemplate and jackson(I think it should be jackson-all) jars in your project.  You can find links to those jars in RestTemplate documentation(link above). 
To make this asynchronous use  AsyncTask from Android SDK.