<p>The In-app Billing Version 3 API makes it easier for you to integrate In-app Billing into your applications. The features in this version include improved synchronous purchase flow, APIs to let you easily track ownership of consumable goods, and local caching of in-app purchase data.</p>
<h2 id="producttypes">Product Types</h2>
<p>You define your products using the Google Play Developer Console, including product type, SKU, price, description, and so on. For more information, see <a
href="{@docRoot}google/play/billing/billing_admin.html">Administering In-app Billing</a>. The Version 3 API supports managed in-app products and subscriptions.</p>
<p>Managed in-app products are items that have their ownership information tracked and managed by Google Play. When a user purchases a managed in-app item, Google Play stores the purchase information for each item on a per-user basis. This enables you to later query Google Play at any time to restore the state of the items a specific user has purchased. This information is persistent on the Google Play servers even if the user uninstalls the application or if they change devices.</p>
<p>If you are using the Version 3 API, you can also consume managed items within your application. You would typically implement consumption for items that can be purchased multiple times (such as in-game currency, fuel, or magic spells). Once purchased, a managed item cannot be purchased again until you consume the item, by sending a consumption request to Google Play. To learn more about in-app product consumption, see <a href="#consume">Consuming Items</a></p>
<strong>Figure 1.</strong> The basic sequence for a purchase request.
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<p>A typical purchase flow with the Version 3 API is as follows:
<ol>
<li>Your application sends a {@code isBillingSupported} request to Google Play to determine that the target version of the In-app Billing API that you are using is supported. </li>
<li>When your application starts or user logs in, it's good practice to check with Google Play to determine what items are owned by the user. To query the user's in-app purchases, send a {@code getPurchases} request. If the request is successful, Google Play returns a {@code Bundle} containing a list of product IDs of the purchased items, a list of the individual purchase details, and a list of the signatures for the purchases.</li>
<li>Usually, you'll want to inform the user of the products that are available for purchase. To query the details of the in-app products that you defined in Google Play, your application can send a {@code getSkuDetails} request. You must specify a list of product IDs in the query request. If the request is successful, Google Play returns a {@code Bundle} containing product details including the product’s price, title, description, and the purchase type.
</li>
<li>If an in-app product is not owned by the user, you can initiate a purchase for it. To start a purchase request, your application sends a {@code getBuyIntent} request, specifying the product ID of the item to purchase, along with other parameters. You should record the product ID when you create a new in-app product in the Developer Console.
<ol type="a">
<li>Google Play returns a {@code Bundle} that contains a {@code PendingIntent} which you application uses to start the checkout UI for the purchase.</li>
<li>Your application launches the pending intent by calling the {@code startIntentSenderForResult} method.</li>
<li>When the checkout flow finishes (that is, the user successfully purchases the item or cancels the purchase), Google Play sends a response {@code Intent} to your {@code onActivityResult} method. The result code of the {@code onActivityResult} has a result code that indicates whether the purchase was successful or canceled. The response {@code Intent} contains information about the purchased item, including a {@code purchaseToken} String that is generated by Google Play to uniquely identify this purchase transaction. The {@code Intent} also contains the signature of the purchase, signed with your private developer key.</li>
</ol>
</li>
</ol>
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<p>To learn more about the Version 3 API calls and server responses, see <a href="{@docRoot}google/play/billing/billing_reference.html">In-app Billing Reference</a>.</p>
<p>To retrieve the list of product's owned by the user, your application sends a {@code getPurchases} call to Google Play. Your application can make a consumption request by sending a {@code consumePurchase} call. In the request argument, you must specify the in-app product's unique {@code purchaseToken} String that you obtained from Google Play when it was purchased. Google Play returns a status code indicating if the consumption was recorded successfully.</p>
<dd>Typically, you would not implement consumption for in-app products that can only be purchased once in your application and provide a permanent benefit. Once purchased, these items will be permanently associated to the user's Google account. An example of a non-consumable in-app product is a premium upgrade or a level pack.</dd>
<dd>In contrast, you can implement consumption for items that can be made available for purchase multiple times. Typically, these items provide certain temporary effects. For example, the user's in-game character might gain life points or gain extra gold coins in their inventory. Dispensing the benefits or effects of the purchased item in your application is called <em>provisioning</em> the in-app product. You are responsible for controlling and tracking how in-app products are provisioned to the users.
<p class="note"><strong>Important:</strong> Before provisioning the consumable in-app product in your application, you must send a consumption request to Google Play and receive a successful response indicating that the consumption was recorded.</p>
<p>Subsequently, when the user starts up or logs in to your application, you should check if the user owns any outstanding consumable in-app products; if so, make sure to consume and provision those items. Here's the recommended application startup flow if you implement consumable in-app products in your application:</p>
<li>Send a {@code getPurchases} request to query the owned in-app products for the user.</li>
<li>If there are any consumable in-app products, consume the items by calling {@code consumePurchase}. This step is necessary because the application might have completed the purchase order for the consumable item, but stopped or got disconnected before the application had the chance to send a consumption request.</li>
<li>Get a response code from Google Play indicating if the consumption completed successfully.</li>
<li>If the consumption was successful, provision the product in your application.</li>
</ol>
<h2 id="caching">Local Caching</h2>
<p>Because the Google Play client now caches In-app Billing information locally on the device, you can use the Version 3 API to query for this information more frequently, for example through a {@code getPurchases} call. Unlike with previous versions of the API, many Version 3 API calls will be serviced through cache lookups instead of through a network connection to Google Play, which significantly speeds up the API's response time. </p>
