About subscriptions

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This document describes how to handle subscription lifecycle events, such as renewals and expirations. It also describes additional subscription features such as offering promotions and allowing your users to manage their own subscriptions.

If you haven't configured subscription products for your app, see Create and configure your products.

Subscriptions overview

A subscription is a recurring transaction that grants specific entitlements to users. The entitlements represent a set of benefits users can access during a specified time period. For example, a subscription might entitle a user for a premium access.

Through base plans and offers, you can create multiple configurations for the same subscription product. For example, you can create an introductory offer for users who have never subscribed to your app. Similarly, you can create an upgrade offer for users who are already subscribed.

For a detailed overview of subscription products, base plans, and offers, see the documentation in the Play Console Help Center.

The Play Billing Library supports the following subscription types:

• Single-item subscription - In this type, one item corresponding to one entitlement. For example, subscription to a music streaming service.

• Subscription with add-ons - In this type, one purchase can have several distinct entitlements bundled in a single purchase. For example, subscription to both music streaming service, and a video subscription. For information specific to subscription with add-ons, see Subscriptions with add-ons.

Prepaid plans integration

Prepaid plans do not automatically renew upon expiration. To extend their subscription entitlement without interruption, the user must top-up a prepaid plan for the same subscription.

For top-ups, launch the billing flow as you would with the original purchase. You don't need to indicate that a purchase is a top-up.

Prepaid plan top-ups always use the CHARGE_FULL_PRICE replacement mode, and you don't need to set this mode explicitly. The user is immediately charged for a full billing period, and their entitlement is extended by the duration specified in the top-up.

After a top-up, the following fields in the Purchase result object are updated to reflect the most recent top-up purchase:

• Order id
• Purchase time
• Signature
• Purchase token
• Acknowledged

The following Purchase fields always contain the same data found in the original purchase:

• Package name
• Purchase state
• Products
• Auto renewing

Prepaid purchase acknowledgement

Similar to auto-renewing subscriptions, you must acknowledge prepaid plans after purchase. Both the initial purchase and any top-ups need to be acknowledged. For more information, see Processing purchases.

Due to the potential for short prepaid plan durations, it is important to acknowledge the purchase as soon as possible.

Prepaid plans with a duration of one week or longer must be acknowledged within three days.

Prepaid plans with a duration shorter than one week must be acknowledged within half the plan duration. For example, developers have 1.5 days to acknowledge a three-day prepaid plan.

Installment subscriptions integration

An installment subscription is a type of subscription where users pay for the subscription in multiple installments over a period of time, rather than paying the entire subscription fee upfront.

Additional considerations for installment subscriptions:

• Country availability: Installment subscriptions feature is only available in Brazil, France, Italy, and Spain (check Console for latest availability).
• Setting the price: When setting the price for an installment subscription on the Console, the price represents the monthly payment amount. This, combined with the commitment period that is set, generates the total amount for the subscription in the purchase screen.
• Commitment period: The total duration of the initial subscription commitment, during which monthly payments are required. For example, if a base plan has a 15-month commitment period, the user will make 15 monthly payments over this period.
• Renewals: In the context of installment subscriptions, "renewal" signifies the conclusion of a commitment period, either initial commitment period or subsequent commitment period. Following the initial sign up, the first renewal occurs upon completion of the entire initial commitment period. Subsequent renewals occur after each subsequent commitment period is fulfilled. The renewal types for installment subscriptions can be "auto-renews monthly" or "auto-renews for the same duration". For "auto-renews monthly", there is no subsequent commitment and the plan behaves like a monthly subscription where each monthly subscription charge constitutes a renewal.
• Billing period: In the context of installment subscriptions, this refers to the recurring interval at which individual payments are made, as specified in the base plan.
• Plan change vs. price change behaviors: For price changes and cancellations, the commitment is firm. This means that if a user wants to cancel or a developer wants to change the price, the change takes effect at the end of a commitment period. For plan changes, the commitment is not firm. This means that the plan change does not have to wait until the end of a commitment period, it takes effect either immediately or on the next payment date based on the set replacement mode.
• Same-subscription plan change: Plan change from an installments base plan to a non-installments base plan of the same subscription product is not allowed.

• Real-time developer notifications (RTDNs): A SUBSCRIPTION_CANCELLATION_SCHEDULED RTDN is sent immediately upon user-initiated cancellation when payments remain for the commitment period. The cancellation is pending and will only take effect at the end of the commitment period. Then, if not restored by the user, SUBSCRIPTION_CANCELED and SUBSCRIPTION_EXPIRED RTDNs are sent at the end of the commitment period.

• Payouts / Revenue realization: Developer payouts will happen as users make their monthly payments, subject to the same terms as all other subscriptions. Developers are not paid upfront when the user signs up for the installment subscription.

• Missed payment collections: If a user fails to make any installment subscription payments, neither Google nor Developer will attempt to collect any such missed or outstanding payments from the user, except that Google may periodically retry the payment during any applicable Grace Period or Account Hold period in accordance with its normal payment retry practices. Google will not be responsible to the Developer for any remaining unpaid installment payments.

• Play Billing Library availability: The installmentDetails field is only available for PBL 7 or later. For PBL 5 and later, the installment subscription is returned using queryProductDetails(), but the subscription won't include detailed installment information like committed payments count of the plan.

Use deep links to allow users to manage a subscription

Your app should include a link on a settings or preferences screen that allows users to manage their subscriptions, which you can incorporate into your app's natural look and feel.

You can include a deep link from your app to the Google Play subscriptions center for non-expired subscriptions, which you can determine using the subscriptionState field of the subscription resource. Based on this, there are several ways you can deep link into the Play Store subscriptions center.

Link to the subscriptions center

Use the following URL to direct users to the page that shows all of their subscriptions, as shown in figures 1 and 2:

https://play.google.com/store/account/subscriptions

This deep link could be useful to help a user restore a canceled subscription from the Play Store subscriptions center.

Link to a specific subscription management page (recommended)

To directly link to the management page for a non-expired subscription, indicate the package name and productId associated with the purchased subscription. To programmatically determine the productId for an existing subscription, query your app's backend or call BillingClient.queryPurchasesAsync() for a list of subscriptions associated with a particular user. Each subscription contains the corresponding productId as part of the subscription status information. Each SubscriptionPurchaseLineItem object associated with a subscription purchase contains the productId value associated with the subscription that the user purchased in that line item.

Use the following URL to direct users to a specific subscription management screen, replacing "your-sub-product-id" and "your-app-package" with the productId and app package name respectively:

https://play.google.com/store/account/subscriptions?sku=your-sub-product-id&package=your-app-package

The user is then able to manage their payment methods and access features including cancellation, resubscription, and pause.

Allow users to upgrade, downgrade, or change their subscription

You can provide existing subscribers with various options to change their subscription plan to better meet their needs:

• If you sell multiple subscription tiers, such as "basic" and "premium" subscriptions, you can allow users to switch tiers by purchasing a different subscription's base plan or offer.
• You can allow users to change their current billing period, such as switching from a monthly to an annual plan.
• You can also allow users to switch between auto-renewing and prepaid plans.

You can encourage any of these changes by providing subscription offers to provide a discount to eligible users. For example, you could create an offer providing a 50% discount on the first year when switching from a monthly to an annual plan, and limit this offer to users subscribed to a monthly plan who haven't purchased this offer. More information on offer eligibility criteria is available in the Help Center

Figure 3 shows an example app with three different plans:

Your app could show a screen similar to figure 3, giving users options to change their subscription. In all cases, it should be clear to users what their current subscription plan is, and what options they have for changing it.

When users decide to upgrade, downgrade, or change their subscription, you specify a replacement mode that determines how the prorated value of the current paid billing period is applied, and when any entitlement change occurs.

Replacement modes

The following table lists available replacement modes and example usage, and count of payments considered paid.

To learn more about different upsell and winback applications of upgrade or downgrade offers, read the offers and promotions guide.

Set the replacement mode for a purchase

You can use different replacement modes for different types of subscription transitions, based on your preferences and business logic. This section explains how to set a replacement mode for a change in a subscription and the limitations that apply.

Resubscribe or switch plans within the same subscription

You can specify a default replacement mode in the Google Play Console. This setting lets you choose when to charge current subscribers if they purchase a different base plan or offer for the same subscription or resubscribe after a cancellation. The available options are Charge immediately, equivalent to CHARGE_FULL_PRICE, and Charge at the next billing date, equivalent to WITHOUT_PRORATION. These are the only relevant replacement modes when switching base plans within the same subscription.

For example, if you are implementing a winback offer for the same plan after the user cancels but before the subscription ends, you can process the new purchase as a regular purchase without indicating any values in SubscriptionUpdateParams. The system uses the default replacement mode you configured in the subscription and automatically handles the plan transition from the old purchase to the new purchase.

Switch plans across subscriptions, or override the default replacement mode

If the user is changing subscription products—purchasing a different subscription—or if you want to override the default replacement mode for any reason, you specify the proration rate at runtime as part of the purchase flow parameters.

To correctly provide SubscriptionUpdateParams as part of your runtime purchase flow configuration, note the following restrictions:

• When upgrading, downgrading, or initiating doing a same-subscription switch to a prepaid plan from either a prepaid plan, auto-renewing plan, or installment plan, the only allowed replacement mode is CHARGE_FULL_PRICE. If you specify any other replacement mode, the purchase fails and an error is shown to the user.
• When switching plans within the same subscription to an auto-renewing plan from either a prepaid plan or an auto-renewing plan, valid proration modes are CHARGE_FULL_PRICE and WITHOUT_PRORATION. If you specify any other proration mode, the purchase fails and an error is shown to the user.
• Switching plans within the same subscription product from an installments base plan to a non-installments base plan is not allowed.

Replacement examples and behaviors

To understand how each proration mode works, consider the following scenario:

Samwise has a subscription to online content from the Country Gardener app. He has a monthly subscription to the Tier 1 version of the content, which is text-only. This subscription costs him $2 per month, and it renews on the first of the month.

On April 15, Samwise chose to upgrade to the annual version of the Tier 2 subscription, which includes video updates and costs $36 per year.

When upgrading the subscription, the developer selects a proration mode. The following list describes how each proration mode affects Samwise's subscription:

WITH_TIME_PRORATION

Samwise's Tier 1 subscription ends immediately. Because he paid for a full month (April 1-30) but upgraded halfway through the subscription period, half of a month's subscription ($1) is applied to his new subscription. However, because that new subscription costs $36 per year, the $1 credit balance pays for only 10 days (April 16-25); so on April 26, he is charged $36 for a new subscription and another $36 on April 26th of each year following.

You should call your app's PurchasesUpdatedListener the moment the purchase succeeds, and you are able to retrieve the new purchase as part of a queryPurchasesAsync() call. Your backend immediately receives a SUBSCRIPTION_PURCHASED Real Time Developer Notification.

CHARGE_PRORATED_PRICE

This mode can be used because the Tier 2 subscription price per time unit ($36/year = $3/month) is greater than the Tier 1 subscription price per time unit ($2/month). Samwise's Tier 1 subscription ends immediately. Because he paid for a full month but used only half of it, half of a month's subscription ($1) is applied to his new subscription. However, because that new subscription costs $36/year, the remaining 15 days costs $1.50; so he is charged the difference of $0.50 for his new subscription. On May 1st, Samwise is charged $36 for his new subscription tier and another $36 on May 1 of each year following.

You should call your app's PurchasesUpdatedListener the moment the purchase succeeds, and you are able to retrieve the new purchase as part of a queryPurchasesAsync() call. Your backend immediately receives a SUBSCRIPTION_PURCHASED Real Time Developer Notification.

WITHOUT_PRORATION

Samwise's Tier 1 subscription is immediately upgraded to Tier 2 with no extra charge, and on May 1st he is charged $36 for his new subscription tier and another $36 on May 1 of each year following.

You should call your app's PurchasesUpdatedListener the moment the purchase succeeds, and you are able to retrieve the new purchase as part of a queryPurchasesAsync() call. Your backend immediately receives a SUBSCRIPTION_PURCHASED Real Time Developer Notification.

DEFERRED

Samwise's Tier 1 subscription continues until it expires on April 30. On May 1st, the Tier 2 subscription takes effect, and Samwise is charged $36 for his new subscription tier.

You should call your app's PurchasesUpdatedListener the moment the purchase succeeds, and you are able to retrieve the new purchase as part of a queryPurchasesAsync() call. Your backend immediately receives a SUBSCRIPTION_PURCHASED Real Time Developer Notification. You should process the purchase the same way you would process any other new purchase at that point. In particular, make sure you acknowledge the new purchase. Note that the startTime of the new subscription is populated at the moment the replacement is effective, which happens when the old subscription expires. At that point, you receive a SUBSCRIPTION_RENEWED RTDN for the new subscription plan. Read more about the ReplacementMode.DEFERRED behavior in Handle deferred replacement.

CHARGE_FULL_PRICE

Samwise's Tier 1 subscription ends immediately. His Tier 2 subscription begins today and he is charged $36. Because he paid for a full month but used only half of it, half of a month's subscription ($1) is applied to his new subscription. Because that new subscription costs $36/year, he would get 1/36th of a year added on to his subscription period (~10 days). Therefore, Samwise's next charge would be 1 year and 10 days from today for $36. After that, he is charged $36 each year following.

When choosing a proration mode, be sure to review our replacement recommendations.

Trigger subscription changes in-app

Your app can offer users an upgrade or downgrade using the same steps as with launching a purchase flow. However, when upgrading or downgrading, you need to provide details for the current subscription, the future (upgraded or downgraded) subscription, and the replacement mode to use, as shown in the following example:

val offerToken = productDetails
        .getSubscriptionOfferDetails(selectedOfferIndex)
        .getOfferToken()

val billingParams = BillingFlowParams.newBuilder().setProductDetailsParamsList(
       listOf(
           BillingFlowParams.ProductDetailsParams.newBuilder()
               .setProductDetails(productDetails)
               .setOfferToken(offerToken)
               .build()
       )
       ).setSubscriptionUpdateParams(
           BillingFlowParams.SubscriptionUpdateParams.newBuilder()
               .setOldPurchaseToken("old_purchase_token")
               .setSubscriptionReplacementMode(
                 BillingFlowParams.ReplacementMode.CHARGE_FULL_PRICE
               )
               .build()
       ).build()

billingClient.launchBillingFlow(
    activity,
    billingParams
   )
// ...

String offerToken = productDetails
    .getSubscriptionOfferDetails(selectedOfferIndex)
    .getOfferToken();

BillingFlowParams billingFlowParams = BillingFlowParams.newBuilder()
    .setProductDetailsParamsList(
        ImmuableList.of(
            ProductDetailsParams.newBuilder()
                // fetched via queryProductDetailsAsync
                .setProductDetails(productDetails)
                // offerToken can be found in
                // ProductDetails=>SubscriptionOfferDetails
                .setOfferToken(offerToken)
                .build()))
    .setSubscriptionUpdateParams(
        SubscriptionUpdateParams.newBuilder()
            // purchaseToken can be found in Purchase#getPurchaseToken
            .setOldPurchaseToken("old_purchase_token")
            .setSubscriptionReplacementMode(ReplacementMode.CHARGE_FULL_PRICE)
            .build())
    .build();

BillingResult billingResult = billingClient.launchBillingFlow(activity, billingFlowParams);
// ...

Replacement recommendations

The following table shows diferrent proration scenarios along with what we recommend for each scenario:

Handle subscription change purchases

Changes of plan are new purchases for all terms and purposes, and they should be processed and acknowledged as such after the billing flow completes successfully. In addition to processing the new purchase appropriately, you have to retire the purchase that is being replaced.

The in-app behavior is the same as for any new purchase. Your app receives the outcome of the new purchase in your PurchasesUpdatedListener, and the new purchase is available in queryPurchasesAsync.

The Google Play Developer API returns a linkedPurchaseToken in the subscription resource when a purchase replaces an existing one. Be sure to invalidate the token provided in the linkedPurchaseToken to ensure that the old token is not used to gain access to your services. See Upgrades, downgrades, and resignups for information on handling upgrade and downgrade purchases.

When you receive the new purchase token, follow the same verification process as with verifying a new purchase token. Make sure to acknowledge these purchases with BillingClient.acknowledgePurchase() from the Google Play Billing Library or Purchases.subscriptions:acknowledge from the Google Play Developer API.

Handle deferred replacement

Deferred replacement mode lets you let a user use up the remaining entitlement in their old plan before starting on the new plan.

When you use ReplacementMode.DEFERRED for a new purchase, queryPurchasesAsync() returns a new purchase token after the purchase flow that remains associated with the old product until the deferred replacement takes place on the next renewal date, after which the new product is returned.

In the past you could achieve this user experience with the deprecated ProrationMode.DEFERRED, but ProrationMode.DEFERRED is deprecated with Play Billing Library 6. See the following table to understand where the behavior differs:

ReplacementMode.DEFERRED should be used from now on instead of the deprecated ProrationMode.DEFERRED, as it presents the same behavior regarding entitlement changes, but offers a way to manage the purchase that is more consistent with behaviors for other new purchases.

Customer management

Using Real-time developer notifications, you can detect in real time when a user decides to cancel. When a user cancels, but before their subscription has expired, you can send them push notifications or in-app messages to ask them to resubscribe.

After a user has cancelled their subscription, you can try to win them back either in your app, or through the Play store. The following table describes various subscription scenarios along with associated winback actions and app requirements.

Before subscription expiration - in-app

For subscriptions that have been canceled but have not yet expired, you can allow subscribers to restore their subscription within your app by applying the same in-app product purchase flow as for new subscribers. Ensure your UI reflects that the user has an existing subscription. For example, you might want to display the user's current expiration date and recurring price with a Reactivate button.

Most of the time, you will want to offer the user the same price and SKU they were already subscribed to, as follows:

• Initiate a new subscription purchase with the same SKU.
• The new subscription replaces the old one and renews on the same expiration date. The old subscription is immediately marked as expired.
• As an example, Achilles has a subscription to Example Music App, and the subscription is due to expire on August 1. On July 10, he resubscribes to the one-month subscription at the same price per month. The new subscription is prorated with the remaining credit, is immediately active, and still renews on August 1.

If you would like to offer a different price—for example a new free trial or a winback discount—you can instead offer a different SKU to the user:

• Initiate an upgrade or downgrade with the different SKU using the replacement mode WITHOUT_PRORATION.
• The new subscription replaces the old one and renews on the same expiration date. The user is charged the price of the new SKU, including any introductory prices, on the original expiration date. If the old subscription was created using an obfuscated account id, that same id should be passed to the BillingFlowParams for upgrades and downgrades.
• As an example, Achilles has a subscription to Example Music App, and the subscription is due to expire on August 1. On July 10, he resubscribes to an annual subscription with an introductory price. The new subscription is immediately active, and the user is charged the introductory price on August 1.
• If you decide to include a free trial or intro price in your winback SKU, ensure that the user is eligible by unchecking the Allow one free trial per app box in the Google Play Console, which restricts the user to getting one free trial per app.

When you receive the purchase token, process the purchase just as you would with a new subscription. Additionally, the Google Play Developer API returns a linkedPurchaseToken in the subscription resource. Be sure to invalidate the token provided in the linkedPurchaseToken to ensure that the old token is not used to gain access to your services.

Before subscription expiration - in Play Store

While the subscription is canceled but still active, users can restore the subscription in the Google Play subscriptions center by clicking Resubscribe (previously Restore). This keeps the same subscription and purchase token.

For more information on restoring subscriptions, see Restorations.

After subscription expiration - in-app

You can allow expired subscribers to resubscribe within your app by applying the same in-app product purchase flow as for new subscribers. Note the following:

• To offer users a discount, you might want to offer a product ID with special pricing for your subscription, also called a winback SKU. You can provide the offer in your app, or you can notify the user of the offer outside of the app, such as in email.
• To start a winback subscription, launch the purchase flow in your Android app using the Google Play Billing Library. This is the same process as with a new subscription, but you can determine the SKU that is available to the user.
• If you decide to include a free trial or intro price in your winback SKU, ensure that the user is eligible by unchecking the Allow one free trial per app box in the Google Play Console, which restricts the user to getting one free trial per app.
• If the user resubscribes to the same SKU, they are no longer eligible for free trials or introductory price. Ensure that your UI reflects this.

When you receive the purchase token, process the purchase just as you would with a new subscription. You will not receive a linkedPurchaseToken in the subscription resource.

After subscription expiration - in Play Store

If enabled, users can resubscribe to the same SKU for up to one year after expiration by clicking Resubscribe in the Google Play subscriptions center. This generates a new subscription and purchase token.

Resubscribing is considered an out-of-app purchase, so be sure to follow best practices for handling purchases made from outside your app.

Promote your subscription

You can create promotion codes to give selected users an extended free trial to an existing subscription. To learn more, see Promo codes.

For free trials, Google Play verifies that the user has a valid payment method before starting the free trial. Some users may see this verification as a hold or charge on their payment method. This hold or charge is temporary and is later reversed or refunded.

After the trial period ends, the user's payment method is charged for the full subscription amount.

If a user cancels a subscription at any time during the free trial, the subscription remains active until the end of the trial, and they aren't charged when the free trial period ends.

Cancel, refund, or revoke

You can use the Google Play Developer API to cancel, refund, or revoke a subscription. This functionality is also available in the Google Play Console.

• Cancel: Users can cancel a subscription on Google Play. You can also provide an option for users to cancel in your app or on your website. Your app should handle these cancellations as described in Cancellations.
• Refund: When you refund, the user can continue to use the subscription. Refunds can be used if, for example, there was a technical error that prevented the user from accessing your product, but the error has been resolved. Note that to refund more than the most recent payment, or if you want to issue a partial refund, you must use the Google Play Console.
• Revoke: When you revoke, the user immediately loses access to the subscription. This can be used if, for example, there was a technical error that prevented the user from accessing your product, and the user does not want to continue using the product. Your app should handle these cancellations as described in Revocations.

The following table illustrates the differences between cancel, refund, and revoke.

Defer billing for a subscriber

You can advance the next billing date for an auto-renewing subscriber by using Purchases.subscriptions:defer from the Google Play Developer API. During the deferral period, the user is subscribed to your content with full access but is not charged. The subscription renewal date is updated to reflect the new date.

For prepaid plans, you can use the defer billing API to defer the expiration time.

Deferred billing allows you to do the following:

• Give users free access as a special offer, such as giving one week free for purchasing a movie.
• Give free access to customers as a gesture of goodwill.

Billing can be deferred by as little as one day and by as long as one year per API call. To defer the billing even further, you can call the API again before the new billing date arrives.

As an example, Darcy has a monthly subscription to online content for the Fishing Quarterly app. She is normally billed £1.25 on the first of each month. In March, she participated in an online survey for the app publisher. The publisher rewards her with six free weeks by deferring the next payment until May 15, which is six weeks after her previously scheduled billing date of April 1. Darcy is not charged for April or the beginning of May and still has access to the content. On May 15, she is charged the normal £1.25 subscription fee for the month. Her next renewal date is now June 15.

When deferring, you might want to notify the user by email or within the app to notify them that their billing date has changed.

Handling payment declines

If there are payment issues with a subscription renewal, Google will periodically attempt to renew the subscription for some time before canceling. This recovery period can consists of a grace period, followed by an account hold period. During this time, Google sends the user emails and notifications prompting them to update their payment method.

Upon payment decline, the subscription enters a grace period if one is configured. During the grace period, you should ensure the user still has access to the subscription entitlements.

After any grace period has ended, the subscription enters an account hold period. During account hold, you should ensure the user does not have access to the subscription entitlements.

You can specify the length of each auto-renewing base plan's grace period and account hold in the Google Play Console. Specifying lengths less than the default values may reduce the number of subscriptions recovered from payment declines.

To maximize the likelihood of subscription recovery during a payment decline, you can inform your user of a payment issue and ask them to fix it.

You can either do this yourself, as described in the grace period and account hold sections, or you can implement the in-app messaging API, where Google shows a message to users in your app.

In-app messaging

If you've enabled in-app messaging with InAppMessageCategoryId.TRANSACTIONAL, Google Play will show users messaging during grace period and account hold once per day and provide them an opportunity to fix their payment without leaving the app.

We recommend that you call this API whenever the user opens the app to determine whether the message should be shown.

If the user successfully recovered their subscription, you will receive a response code of SUBSCRIPTION_STATUS_UPDATED along with a purchase token. You should then use this purchase token to call the Google Play Developer API and refresh the subscription status in your app.

Integrate in-app messaging

To show in-app messaging to user, use BillingClient.showInAppMessages().

Here is an example of triggering the in-app messaging flow:

val inAppMessageParams = InAppMessageParams.newBuilder()
        .addInAppMessageCategoryToShow(InAppMessageCategoryId.TRANSACTIONAL)
        .build()

billingClient.showInAppMessages(activity,
        inAppMessageParams,
        object : InAppMessageResponseListener() {
            override fun onInAppMessageResponse(inAppMessageResult: InAppMessageResult) {
                if (inAppMessageResult.responseCode == InAppMessageResponseCode.NO_ACTION_NEEDED) {
                    // The flow has finished and there is no action needed from developers.
                } else if (inAppMessageResult.responseCode
                        == InAppMessageResponseCode.SUBSCRIPTION_STATUS_UPDATED) {
                    // The subscription status changed. For example, a subscription
                    // has been recovered from a suspend state. Developers should
                    // expect the purchase token to be returned with this response
                    // code and use the purchase token with the Google Play
                    // Developer API.
                }
            }
        })

InAppMessageParams inAppMessageParams = InAppMessageParams.newBuilder()
        .addInAppMessageCategoryToShow(InAppMessageCategoryId.TRANSACTIONAL)
        .build();

billingClient.showInAppMessages(activity,
        inAppMessageParams,
        new InAppMessageResponseListener() {
            @Override
            public void onInAppMessageResponse(InAppMessageResult inAppMessageResult) {
                if (inAppMessageResult.responseCode
                        == InAppMessageResponseCode.NO_ACTION_NEEDED) {
                    // The flow has finished and there is no action needed from developers.
                } else if (inAppMessageResult.responseCode
                        == InAppMessageResponseCode.SUBSCRIPTION_STATUS_UPDATED) {
                    // The subscription status changed. For example, a subscription
                    // has been recovered from a suspend state. Developers should
                    // expect the purchase token to be returned with this response
                    // code and use the purchase token with the Google Play
                    // Developer API.
                }
            }
        });

Handle subscription pending transactions

Pending transactions can happen in initial purchase, top-up, upgrade or downgrade. The subscription purchase starts with the SUBSCRIPTION_STATE_PENDING state before transitioning to SUBSCRIPTION_STATE_ACTIVE. If the transaction is expired or canceled by the user, it goes to SUBSCRIPTION_STATE_PENDING_PURCHASE_EXPIRED. You must and should only update the user's entitlement after the transaction is completed.

Subscription state change for initial purchase with pending transactions is straightforward. Your app receives a Purchase with PENDING state when the user initiates a pending transaction. When the transaction is completed, your app receives the Purchase again with state updated to PURCHASED. A SubscriptionNotification message with type SUBSCRIPTION_PURCHASED is sent to your RTDN client. Follow the normal process to verify the purchase, give the user access to the content and acknowledge the purchase. If the transaction expires or is canceled, a SubscriptionNotification message with type SUBSCRIPTION_PENDING_PURCHASE_CANCELED is sent to your RTDN client. In such cases, the user should never have gained access to the content.

Top-up, upgrade or downgrade with pending transactions involves state changes for both the old and new subscriptions. When the user initiates a pending top-up, upgrade or downgrade transaction, your app receives a Purchase for the old subscription with a PendingPurchaseUpdate object. At this time, the user is still owning the old subscription and has not gained the new subscription yet. Calling getProducts() and getPurchaseToken() on the PendingPurchaseUpdate object returns the product ids and purchase token of the new subscription. When the transaction is completed, your app receives a Purchase with the top-level purchase token set for the new subscription and the state set to PURCHASED. A SubscriptionNotification message with type SUBSCRIPTION_PURCHASED is sent to your RTDN client. Only at this time, you should replace the old purchase token with the new purchase token and update the user's access to the content. If the transaction expires or is canceled, a SubscriptionNotification message with type SUBSCRIPTION_PENDING_PURCHASE_CANCELED is sent to your RTDN client. In such cases, the user should still have access to the content of the old subscription.