docs: Documented new IABv5 sub upgrade/downgrade and manual renewal

Documented new support for users upgrading/downgrading subscriptions
in the middle of a sub period, and for users manually renewing
before the subscription period ends. Also updated testing docs
to reflect that sandbox now supports testing subscriptions, and
documented new "autoRenewing" field in INAPP_PURCHASE_DATA.

See first comment for doc stage location.

bug: 18982828
bug: 18916814
bug: 18951608
bug: 18908756
Change-Id: I530b57d840ed5aeefe4c6a688a2e59aec41ec7d0
diff --git a/docs/html/google/play/billing/billing_reference.jd b/docs/html/google/play/billing/billing_reference.jd
index da9178d..01e680f 100644
--- a/docs/html/google/play/billing/billing_reference.jd
+++ b/docs/html/google/play/billing/billing_reference.jd
@@ -12,6 +12,7 @@
     <ol>
       <li><a href="#getSkuDetails">getSkuDetails()</a></li>
       <li><a href="#getBuyIntent">getBuyIntent()</a></li>
+      <li><a href="#upgrade-getBuyIntentToReplaceSkus">getBuyIntentToReplaceSkus()</a></li>
       <li><a href="#getPurchases">getPurchases()</a></li>
     </ol>
     </li>
@@ -107,8 +108,8 @@
   </tr>
   <tr>
     <td>{@code type}</td>
-    <td>Value must be “inapp” for an in-app product or "subs" for
-subscriptions.</td>
+    <td>Value must be <code>“inapp”</code> for an in-app product or
+      <code>"subs"</code> for subscriptions.</td>
   </tr>
   <tr>
     <td>{@code price}</td>
@@ -140,7 +141,17 @@
 </p>
 
 <h3 id="getBuyIntent">The getBuyIntent() method</h3>
-<p>This method returns a response code integer mapped to the {@code RESPONSE_CODE} key, and a {@code PendingIntent} to launch the puchase flow for the in-app item mapped to the {@code BUY_INTENT} key. When it receives the {@code PendingIntent}, Google Play sends a response {@code Intent} with the data for that purchase order.  The data that is returned in the response {@code Intent} is summarized in table 3.</p>
+<p>
+  This method returns a response code integer mapped to the {@code
+  RESPONSE_CODE} key, and a {@link android.app.PendingIntent} to launch the
+  purchase flow for the in-app item mapped to the {@code BUY_INTENT} key, as
+  described in <a href=
+  "{@docRoot}google/play/billing/billing_integrate.html#purchase">Purchasing an
+  Item</a>. When it receives the {@link android.app.PendingIntent}, Google Play
+  sends a response {@code Intent} with the data for that purchase order. The
+  data that is returned in the response {@code Intent} is summarized in table
+  3.
+</p>
 
 <p class="table-caption" id="purchase-pendingintent-response-table">
 <strong>Table 3.</strong>  Response data from an In-app Billing Version 3 purchase request.</p>
@@ -151,7 +162,7 @@
   </tr>
   <tr>
     <td>{@code RESPONSE_CODE}</td>
-    <td>0 if the purchase was success, error otherwise.</td>
+    <td>Value is <code>0</code> if the purchase was success, error otherwise.</td>
   </tr>
   <tr>
     <td>{@code INAPP_PURCHASE_DATA}</td>
@@ -176,9 +187,22 @@
     <th scope="col">Field</th>
     <th scope="col">Description</th>
   </tr>
+    <tr>
+    <td>{@code autoRenewing}</td>
+    <td>Indicates whether the subscription renews automatically. If
+      <code>true</code>, the subscription is active, and will
+      automatically renew on the next billing date. If <code>false</code>,
+      indicates that the user has canceled the subscription. The user has
+      access to subscription content until the next billing date and will
+      lose access at that time unless they re-enable automatic renewal
+      (or manually renew, as described in
+      <a href="{@docRoot}google/play/billing/billing_subscriptions.html#manual-renewal">Manual
+      Renewal</a>).</td>
+  </tr>
   <tr>
     <td>{@code orderId}</td>
-    <td>A unique order identifier for the transaction. This corresponds to the Google Wallet Order ID.</td>
+    <td>A unique order identifier for the transaction. This identifier
+      corresponds to the Google Wallet Order ID.</td>
   </tr>
   <tr>
     <td>{@code packageName}</td>
@@ -194,7 +218,8 @@
   </tr>
   <tr>
     <td>{@code purchaseState}</td>
-    <td>The purchase state of the order. Possible values are 0 (purchased), 1 (canceled), or 2 (refunded).</td>
+    <td>The purchase state of the order. Possible values are <code>0</code>
+      (purchased), <code>1</code> (canceled), or <code>2</code> (refunded).</td>
   </tr>
   <tr>
     <td>{@code developerPayload}</td>
@@ -202,20 +227,48 @@
   </tr>
   <tr>
     <td>{@code purchaseToken}</td>
-    <td>A token that uniquely identifies a purchase for a given item and user
-    pair. This token may be up to 1,000 characters long.
-    Pass this entire token to other methods, such as when you consume the
-    purchase (as described in
-<a href="{@docRoot}training/in-app-billing/purchase-iab-products.html#Consume">Consume
-    a Purchase</a>). Do not abbreviate or truncate this token.</td>
+    <td>A token that uniquely identifies a purchase for a given item and user pair. </td>
   </tr>
 </table>
 </p>
 
-<h3 id="getPurchases">The getPurchases() method</h3>
-<p>This method returns the current un-consumed products owned by the user. Table 5 lists the response data that is returned in the {@code Bundle}.</p>
-<p class="table-caption" id="getpurchases-response-table">
-<strong>Table 5.</strong> Response data from a {@code getPurchases} request.</p>
+<h3 id="upgrade-getBuyIntentToReplaceSkus">The getBuyIntentToReplaceSkus()
+  method</h3>
+
+<p>This method is used to upgrade or downgrade a subscription purchase. The method
+is similar to <a href="#getBuyIntent"><code>getBuyIntent()</code></a>, except
+that it takes a list of already-purchased SKUs that are to be
+replaced with the SKU being purchased. When the user completes the purchase,
+Google Play cancels the old SKUs and credits the user with the unused value of
+their subscription time on a pro-rated basis. Google Play applies this credit
+to the new subscription, and does not begin billing the user for the new
+subscription until after the credit is used up.</p>
+
+<p>This method was added with version 5 of the in-app billing API. To verify
+that the method is reported, send an <code>isBillingSupported</code> AIDL
+request.</p>
+
+<p class="note"><strong>Note:</strong> You can only use this method for
+subscription purchases. If the passed <code>type</code> parameter is anything
+other than <code>"subs"</code>, the method returns
+<a href="#billing-codes"><code>BILLING_RESPONSE_RESULT_DEVELOPER_ERROR</code></a>.
+Furthermore, the passed SKUs may not include SKUs for seasonal
+subscriptions.</p>
+
+<p>
+  This method returns a response code integer mapped to the {@code
+  RESPONSE_CODE} key, and a {@link android.app.PendingIntent} to launch the
+  purchase flow for the in-app subscription mapped to the {@code BUY_INTENT}
+  key, as described in <a href=
+  "{@docRoot}google/play/billing/billing_integrate.html#purchase">Purchasing an
+  Item</a>. When it receives the {@link android.app.PendingIntent}, Google Play
+  sends a response {@code Intent} with the data for that purchase order. The
+  data that is returned in the response {@code Intent} is summarized in table
+  5.
+</p>
+
+<p class="table-caption" id="upgrade-purchase-pendingintent-response-table">
+<strong>Table 5.</strong> Response data from an In-app Billing Version 5 purchase request.</p>
 <table>
   <tr>
     <th scope="col">Key</th>
@@ -223,7 +276,39 @@
   </tr>
   <tr>
     <td>{@code RESPONSE_CODE}</td>
-    <td>0 if the request was successful, error otherwise.</td>
+    <td>Value is <code>0</code> if the purchase succeeds. If the purchase fails, contains an error
+      code.</td>
+  </tr>
+  <tr>
+    <td>{@code INAPP_PURCHASE_DATA}</td>
+    <td>
+       A String in JSON format that contains details about the purchase order.
+       See <a href="#purchase-data-table">table 4</a> for a description of the JSON fields.
+    </td>
+  </tr>
+  <tr>
+    <td>{@code INAPP_DATA_SIGNATURE}</td>
+    <td>String containing the signature of the purchase data that the developer
+      signed with their private key. The data signature uses the
+      RSASSA-PKCS1-v1_5 scheme.</td>
+  </tr>
+</table>
+</p>
+
+</p>
+
+<h3 id="getPurchases">The getPurchases() method</h3>
+<p>This method returns the current un-consumed products owned by the user. Table 5 lists the response data that is returned in the {@code Bundle}.</p>
+<p class="table-caption" id="getpurchases-response-table">
+<strong>Table 6.</strong> Response data from a {@code getPurchases} request.</p>
+<table>
+  <tr>
+    <th scope="col">Key</th>
+    <th scope="col">Description</th>
+  </tr>
+  <tr>
+    <td>{@code RESPONSE_CODE}</td>
+    <td>Value is <code>0</code> if the request was successful, error otherwise.</td>
   </tr>
   <tr>
     <td>{@code INAPP_PURCHASE_ITEM_LIST}</td>
diff --git a/docs/html/google/play/billing/billing_subscriptions.jd b/docs/html/google/play/billing/billing_subscriptions.jd
index b9b77df..8f55354e 100644
--- a/docs/html/google/play/billing/billing_subscriptions.jd
+++ b/docs/html/google/play/billing/billing_subscriptions.jd
@@ -1,4 +1,4 @@
-page.title=In-App Subscriptions
+page.title=In-app Subscriptions
 parent.title=In-app Billing
 parent.link=index.html
 page.metaDescription=Subscriptions let you sell content or features in your app with automated, recurring billing.
@@ -21,6 +21,11 @@
         Developer API</a>.</li>
     <li>Users purchase your subscriptions from inside your apps, rather than
         directly from Google Play.</li>
+    <li>Users can renew their subscriptions while a current subscription is
+        active.</li>
+    <li>Users can upgrade or downgrade a subscription in the middle of a
+        subscription period. The old subscription's cost is pro-rated, and the
+        unused portion is applied to the replacement subscription.</li>
     <li>You can defer billing for a particular user's subscription, to manage
         accounts or offer rewards.</li>
   </ul>
@@ -206,6 +211,65 @@
 billing errors that may occur. Your backend servers can use the server-side API 
 to query and update your records and follow up with customers directly, if needed.</p>
 
+<h3 id="manual-renewal">Manual Renewal</h3>
+
+<p>With version 5 of the In-app Billing API, users can renew a subscription
+during its active period even if the subscription is not set to
+automatically renew. If the user purchases a subscription while the subscription
+is active, it is extended by the appropriate period at the current rate.</p>
+
+<p>For example, Achilles has a subscription to the <em>Modern Hoplite</em> app.
+His subscription is currently due to expire on August 1. On July 10, he
+purchases a 3-month subscription at the current rate. Those three months are
+added to his existing subscription, so the subscription now expires on November
+1.</p>
+
+<p>It is up to the app to convey this with an appropriate UI. For example, if a
+user does not have an active subscription, the app might have a
+<strong>buy</strong> button, but if the user has a subscription the button might
+say <strong>renew</strong>.</p>
+
+<h3 id="upgrade">Subscription Upgrade/Downgrade</h3>
+
+<p>
+  With version 5 of the In-app Billing API, users can upgrade or downgrade a
+  subscription during its active period. When the user does this, the active
+  subscription is canceled and a new subscription is created. The unused
+  balance of the old subscription is applied on a pro-rated basis to the new
+  subscription. The first billing period for the new subscription begins after
+  that balance is used up. (The new subscription does not need to have a period
+  of the same length as the old one.)
+</p>
+
+<p>For example, Samwise has a subscription to online content from the
+<em>Country Gardener</em> app. He currently has a monthly subscription to the
+Tier 1
+version of the content (which has text-only content). This subscription costs
+him £2/month, and renews on the first of the month. On April
+15, he chooses to upgrade to the Tier 2 subscription (which includes video
+updates), costing £3/month. His Tier 1 subscription is immediately ended.
+Since he paid for a full month (April 1-30), but only used half of it, half of a
+month's subscription (£1) is applied to his new subscription. However, since
+that new subscription costs £3/month, the £1 credit balance only pays for ten
+days. So Samwise's credit pays for his subscription from April 15-25. On April
+26, he is charged £3 for his new subscription, and another £3 on the 26th of
+each month following.</p>
+
+<p class="note">
+  <strong>Note:</strong> The new subscription's billing date depends on when
+  the subscriber's pro-rated credit runs out, so the subscriber cannot upgrade
+  or downgrade to a seasonal subscription, which has fixed and predetermined
+  beginning and end dates.
+</p>
+
+<p>When a user upgrades or downgrades a subscription, your app calls
+<a href="{@docRoot}google/play/billing/billing_reference.html#upgrade-getBuyIntentToReplaceSkus">
+<code>getBuyIntentToReplaceSkus()</code></a>.
+This method is passed the new SKU the user wants to buy, and all
+the old SKUs that are superseded by it. The remaining portions of the old SKUs
+are used to pay for the new subscription, and billing begins when this credit
+is used up.</p>
+
 <h3 id="deferred-billing">Deferred Billing</h3>
 
 <p>Using the
@@ -316,7 +380,7 @@
 
 <p>When the user cancels a subscription, Google Play does not offer a refund for
 the current billing cycle. Instead, it allows the user to have access to the
-cancelled subscription until the end of the current billing cycle, at which time
+canceled subscription until the end of the current billing cycle, at which time
 it terminates the subscription. For example, if a user purchases a monthly
 subscription and cancels it on the 15th day of the cycle, Google Play will
 consider the subscription valid until the end of the 30th day (or other day,
@@ -357,12 +421,12 @@
 <p>If you receive requests for refunds, you can use the
 <a href="{@docRoot}google/play/billing/gp-purchase-status-api.html">Google Play
 Developer API</a> or the Merchant Center to cancel the subscription, verify that it
-is already cancelled, or refund the user's payment without cancelling it. You
+is already canceled, or refund the user's payment without canceling it. You
 can also use the
 <a href="{@docRoot}google/play/billing/gp-purchase-status-api.html">Google
 Play Developer API</a> to <em>refund and revoke</em> a
 user's subscription. If you refund and revoke a subscription, the user's
-subscription is immediately cancelled, and the user's most recent subscription
+subscription is immediately canceled, and the user's most recent subscription
 payment is refunded. (If you want to refund more than the most recent payment,
 you can process additional refunds through the Merchant Center.)</p>
 
@@ -423,7 +487,7 @@
     <li>Remotely query the validity of a specific subscription at any time</li>
     <li>Cancel a subscription</li>
     <li>Defer a subscription's next billing date</li>
-    <li>Refund a subscription payment without cancelling the subscription</li>
+    <li>Refund a subscription payment without canceling the subscription</li>
     <li>Refund and revoke a subscription</li>
   </ul>
 
diff --git a/docs/html/google/play/billing/billing_testing.jd b/docs/html/google/play/billing/billing_testing.jd
index 36456cc..44b3286 100644
--- a/docs/html/google/play/billing/billing_testing.jd
+++ b/docs/html/google/play/billing/billing_testing.jd
@@ -25,8 +25,8 @@
 implementation:</p>
 
 <ul>
-<li>Test purchases, which let test account users make real purchase your published in-app items,
-but without any actual charges to the user accounts.</li>
+<li>Test purchases, which let license-test users purchase your published in-app
+    items, but without any actual charges to their accounts.</li>
 <li>Static billing responses from Google Play, for testing in early development</p>
 </ul>
 
@@ -43,14 +43,13 @@
 
 <p>When your In-app Billing implementation is ready, you can test purchasing of your in-app SKUs in two ways:</p>
 
-<ul>
-<li><strong>Test purchases</strong>, which let your selected license test users
-purchase your in-app products before the app is published, but without any
-resulting charges to the user, and </li>
+<ul> <li><strong>Test purchases</strong>, which let your selected license-test
+users purchase your in-app products without any resulting charges to the user.
+Test purchases can be used in alpha/beta releases or in published apps. </li>
 <li><strong>Real purchases</strong>, which let regular users make real purchases
 of your in-app products with actual charges to the user’s payment instruments.
-In this case, you can use Google Play’s alpha and beta release groups to manage
-the users who can make “live” purchases using your implementation.  </li>
+You can use Google Play’s alpha and beta release groups to manage
+the users who can make live purchases using your implementation.  </li>
 </ul>
 
 <p>The sections below provide more detail about how to use these approaches for
@@ -61,16 +60,21 @@
 <p>Test purchases offer a secure, convenient way to enable larger-scale testing
 of your In-app Billing implementation during development or in preparation for
 launch. They let authorized user accounts make purchases of your in-app products
-through Google Play while the app is still unpublished, without incurring any
-actual charges to the user accounts.</p>
+through Google Play without incurring any actual charges to the user
+accounts.</p>
 
-<p>Once authorized with testing access, those users can side-load your app and
-test the full merchandising, purchase, and fulfillment flow for your products.
+<p>Once authorized for testing access, those users can make purchases without
+being charged.
 Test purchases are real orders and Google Play processes them in the same way as
 other orders. When purchases are complete, Google Play prevents the orders from
 going to financial processing, ensuring that there are no actual charges to user
 accounts, and automatically canceling the completed orders after 14 days. </p>
 
+<p class="note">
+  <strong>Note:</strong> Test subscription purchases recur daily, regardless of
+  the product's subscription period.
+</p>
+
 <h4 id="setup">Setting up test purchases</h4>
 
 <p>It’s easy to set up test purchases&mdash;any user account can be chosen to be
@@ -91,14 +95,13 @@
 
 <p>Once you’ve added the users as license tester accounts and saved the change,
 within 15 minutes those users can begin making test purchases of your in-app
-products. You can then distribute your app to your testers and provide a means
-of getting feedback. </p>
+products.</p>
 
 <p class="note"><strong>Note</strong>: To make test purchases, the license test
 account must be on the user’s Android device. If the device has more than one
 account, the purchase will be made with the account that downloaded the app. If
 none of the accounts has downloaded the app, the purchase is made with the first
-account.Users can confirm the account that is making a purchase by expanding the
+account. Users can confirm the account that is making a purchase by expanding the
 purchase dialog.</p>
 
 <h4 id="tp-account">Test purchases and developer account</h4>
@@ -114,13 +117,13 @@
 with a notice across the center of the purchase dialog, for easy identification.
 </p>
 
-<h4 id="cancelling">Cancelling completed test purchases</h4>
+<h4 id="cancelling">Canceling completed test purchases</h4>
 <p>Google Play accumulates completed test purchases for each user but does not
 pass them on  to financial processing. Over time, it automatically clears out
-the purchases by cancelling them. </p>
+the purchases by canceling them. </p>
 
 <p>In some cases, you might want to manually cancel a test purchase to continue
-testing. For cancelling purchases, you have these options:</p>
+testing. For canceling purchases, you have these options:</p>
 
 <ul>
 <li>Wait for the transactions to expire&mdash;Google Play clears completed test
@@ -130,13 +133,6 @@
 by looking up their order numbers.</li>
 </ul>
 
-<h4 id="requirements">Requirements for using test purchases</h4>
-<p>If you plan to use test purchases, please note the requirements and limitations below: </p>
-<ul>
-<li>Test purchases is only supported for license test accounts when the app is using the In-app Billing v3 API.</li>
-<li>Test purchases are only supported for in-app products, not for in-app subscriptions.</li>
-</ul>
-
 <h3 id="transations">Testing with real transactions</h3>
 <p>As you prepare to launch an app that uses In-app Billing, you can make use of
 Google Play alpha/beta release options to do validation and load testing on your
@@ -276,8 +272,8 @@
 href="{@docRoot}google/play/billing/billing_admin.html#billing-testing-setup">Setting up test
 accounts</a>.</p>
 
-<p>Also, a test account can purchase an item in your product list only if the item is published. The
-application does not need to be published, but the item does need to be published.</p>
+<p>A test account can purchase an item in your product list only if the
+item is published.</p>
 
 <p>To test your In-app Billing implementation with actual purchases, follow these steps:</p>
 
diff --git a/docs/html/google/play/billing/index.jd b/docs/html/google/play/billing/index.jd
index bdbf5c715..47620c8 100644
--- a/docs/html/google/play/billing/index.jd
+++ b/docs/html/google/play/billing/index.jd
@@ -14,6 +14,16 @@
 <div class="sidebox">
   <h2><strong>New in In-App Billing</strong></h2>
   <ul>
+  <li><strong>Subscription Upgrade/Downgrade</strong>&mdash;A user can
+    subscribe to a higher or lower tier of subscription while their current
+    subscription is active. The old subscription is canceled, and the unused
+    portion is applied on a pro-rated basis to the new subscription.</li>
+  <li><strong>Manual Subscription Renewal</strong>&mdash;A user can purchase
+    a subscription at the current rate while their existing subscription is
+    still active. The existing subscription is extended by the appropriate
+    period.</li>
+  <li><strong>IAB Sandbox</strong>&mdash;The In-app Billing Sandbox now supports
+    testing subscription purchases.</li>
   <li><strong>IAB v2 shutdown</strong>&mdash;In-app Billing v2 API is deprecated and will be shut down in January 2015. If your app is still using In-app Billing v2, please migrate to the v3 API as soon as possible.</li>
   <li><strong>Seasonal subscriptions</strong>&mdash;You can now set up a
     recurring <a href="billing_subscriptions.html#user-billing">seasonal
@@ -35,7 +45,6 @@
     subscription ends
     immediately, and his or her most recent subscription payment is
     refunded.</li>
-  <li><strong>In-app Billing Version 3</strong>&mdash;The <a href="{@docRoot}google/play/billing/api.html">latest version</a> of In-app Billing features a synchronous API that is easier to implement and lets you manage in-app products and subscriptions more effectively.</li>
  </ul>
 </div>
 </div>
diff --git a/docs/html/google/play/billing/versions.jd b/docs/html/google/play/billing/versions.jd
index dbe3ea3..aa35501 100644
--- a/docs/html/google/play/billing/versions.jd
+++ b/docs/html/google/play/billing/versions.jd
@@ -11,10 +11,30 @@
 <p>At run time, your app can query the Google Play Store app to determine what version of the API it supports and what features are available. </p>
 
 <ul>
-<li>If you are using in-app  billing version 3, the version information is not directly returned the Google Play. Instead, you can check if Google Play supports the version of the In-app Billing API that you are using by sending a {@code isBillingSupported} request.</li>
+
+<li>If you are using in-app billing version 3 or later, the version information
+is not directly returned by Google Play. Instead, you can check if Google Play
+supports the version of the In-app Billing API that you are using by sending an
+{@code isBillingSupported} request.</li>
+
 <li>If the In-app Billing API version that you are using is earlier than version 3, the version information is returned in the <code>API_VERSION</code> key of the Bundle object passed in the {@code sendBillingRequest} method. For more information, see <a href="{@docRoot}google/play/billing/v2/billing_reference.html#billing-interface-v2">In-app Billing Service Interface</a>.</li>
 </ul>
 
+<h3 id="version_5">In-app Billing version 5</h3>
+<p><em>February 2015</em></p>
+<ul>
+<li>A user can manually extend an existing subscription. The subscription
+is extended by the appropriate amount of time.</li>
+<li>A user can upgrade or downgrade a subscription while it is active. The
+old subscription is canceled, and the unused portion is applied on a pro-rata
+basis to the new subscription.</li>
+</ul>
+
+<h3 id="version_4">In-app Billing version 4</h3>
+
+<p>Version 4 of the In-app Billing API did not introduce any public
+functionality.</p>
+
 <h3 id="version_3">In-app Billing version 3</h3>
 <p><em>February 2013</em></p>
 <ul>