---
title: applicationUsername
framework: storekit
role: symbol
role_heading: Instance Property
path: storekit/skmutablepayment/applicationusername
---

# applicationUsername

A string that associates the transaction with a user account on your service.

## Declaration

```swift
var applicationUsername: String? { get set }
```

## Mentioned in

Implementing promotional offers in your app Generating a signature for promotional offers Restoring purchased products

## Discussion

Discussion Consider assigning a UUID to the applicationUsername property. When this value is a UUID, the App Store server stores it as an appAccountToken. In this scenario, the following happens: In the App Store Server API, the JWSTransactionDecodedPayload object returns the applicationUsername value in the appAccountToken field. In App Store Server Notifications, the JWSTransactionDecodedPayload object returns the applicationUsername value in the appAccountToken field. When you call the verifyReceipt endpoint to verify an App Store receipt, the App Store server returns the applicationUsername value in the app_account_token field of the responseBody.Latest_receipt_info. The sample code below shows how to assign a UUID value to applicationUsername. You may choose to generate the UUID on your server. Assign the value before adding the payment to the payment queue. If you don’t assign a UUID string value to applicationUsername, the App Store server doesn’t persist the value. The value won’t appear in the app_account_token fields in notifications or receipts. important: An applicationUsername property that isn’t a UUID isn’t guaranteed to persist between the time when you add the payment transaction to the queue and when the queue updates the transaction.

## See Also

### Getting and Setting Attributes

- [productIdentifier](storekit/skmutablepayment/productidentifier.md)
- [quantity](storekit/skmutablepayment/quantity.md)
- [requestData](storekit/skmutablepayment/requestdata.md)