Buy App Functionality (In Billing)

Question

I would like to make my app have the option to buy functionality.

Like I made two apps, one paid (full) and one free (with advertisement).

I would like the person clicking to buy to remove the advertisement and add the activities related to paid.

I saw that I have to do this using In Billing, but I only found for purchase and product listing:

List additionalSkuList = new ArrayList();
additionalSkuList.add(SKU_APPLE);
additionalSkuList.add(SKU_BANANA);
mHelper.queryInventoryAsync(true, additionalSkuList,
   mQueryFinishedListener);

And price samples.

IabHelper.QueryInventoryFinishedListener
   mQueryFinishedListener = new IabHelper.QueryInventoryFinishedListener() {
   public void onQueryInventoryFinished(IabResult result, Inventory inventory)
   {
      if (result.isFailure()) {
         // handle error
         return;
       }

       String applePrice =
          inventory.getSkuDetails(SKU_APPLE).getPrice();
       String bananaPrice =
          inventory.getSkuDetails(SKU_BANANA).getPrice();

       // update the UI
   }
}

I would like to do with functionality. To:

• Withdraw advertising
• Add canvas

Anyone knows a cool tutorial that can indicate?

Rerencia: Establishing In-app Billing Products for Sale