Communicating device app with appstore/google play store

I have developed app for android and ipad.

I am working on Titanium-3.1.1 and Android-3.0.

I want the manual functionality for app updates on device as following:

1. On onload event of app, Compare the version of the app-which is on device and same app-which is on google play store(for android),Appstore(for ipad). If version on appstore/google play store is greater than installed app on device then..

2. open the alert with ok and cancel event.

3. If user click on ok event then app on device is upgrade(update) from appstore/google play store with without loss of data.

4. I know in android automatically update facility, But I want the custom code for that.

5. I am putting the way for coding: that code on app onload event

   if((parseFloat(installed Version on device) < parseFloat(appStore/google play store Version))){
           var alert = Ti.UI.createAlertDialog({
               title:'Update now', 
               message:'There is a new version available. Do you want to update now?',
               buttonNames : ['Update','Cancel']
             });
    
           alert.addEventListener('click', function(y){
               if(y.index == 0){
                   //update code for app on device from google play store.....
               }
           });
           alert.show();
        }

   6. I want the proper code for above way...(I don't want push notification)

6. I want update functionality specially for android..

If anybody had done that,Please help me..