> For the complete documentation index, see [llms.txt](https://kb.nssurge.com/surge-knowledge-base/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kb.nssurge.com/surge-knowledge-base/faq/ios-testflight.md).

# Surge iOS TestFlight

By joining Surge iOS TestFlight, you can use the Beta version of Surge iOS, which contains experimental features and may be unstable. It is only recommended for experienced users who enjoy trying new things. All purchased users can register themselves.

1. If you purchased the license from the website or have already bound your email:

Visit [License Management](https://nssurge.com/account) and log in to apply join the TestFlight.

2. If you purchased through the App Store IAP:

Please bind your email in the App's license management page first.

For details, please refer to [Surge iOS Licensing FAQs](/surge-knowledge-base/license/ios-faq.md)

Technical support will not answer inquiries about TestFlight itself. Please refer to Apple's related instructions.

## Frequently Asked Questions

### Why does it say: "Cannot accept this invitation because your Apple account <joe@icloud.com> is already associated with this app"?

Due to TestFlight system limitations, Apple keeps your tester record for about 90 days after you opt out. If you have already joined Surge's TestFlight and wish to change the linked Apple ID through the Opt-out operation, you must wait about 90 days before you can bind another account.

### Can TestFlight versions be bound to App Store accounts in regions where Surge iOS is not available?

No, Apple changed TestFlight's behavior in February 2021, and you must use an Apple ID from a region where Surge is available to install the TestFlight version (i.e., not a Chinese Apple ID).

If you attempt to install in a region where it is not available, you will receive an "The requested App is not available or does not exist" error.

### Is there a relationship between the Apple ID in TestFlight and license email?

The associated Apple ID is determined by the App Store account currently logged into on the iOS device that clicks on the invitation email, and it has nothing to do with the license email (i.e., the email receiving TestFlight invitations).

However, we strongly recommend binding with an Apple ID that matches your license email. Accepting an invitation with a mismatched Apple ID may lead to anomalies when unbinding later (this is an issue on Apple's server side). You can change your license email yourself before joining TestFlight. After you have joined, a new license email is not applied to your TestFlight record; see the question about changing the invitation email below.

### Is the TestFlight version stable?

The goal of TestFlight versions is to test new features. They have a high update frequency but may be less stable. Please provide feedback if you encounter any issues. Severe problems are generally fixed within one to two days. TestFlight also allows you to revert to a previous version if you encounter severe issues.

### What if I don't receive the TestFlight invitation email?

Invitation emails are sent by Apple's servers, and some email accounts may have difficulty receiving them. Please check your spam folder first, then use the Resend Invitation button on the [License Management](https://nssurge.com/account) page.

Please do not opt out and rejoin to get a new email. Opting out does not let you switch to another address right away (see the next question), and the invitation keeps going to the address your TestFlight record was created with.

### How do I change the email that receives the TestFlight invitation?

The invitation email is fixed when you join TestFlight, and Apple provides no way to change it afterwards. Changing your license email later does not change it either.

Each license can hold only one TestFlight seat, and Apple keeps your tester record, together with its email address, for about 90 days after you opt out. During that time you can rejoin, but the invitation can only be sent to the previous address. To use a new address, opt out, wait about 90 days, and then join again with the new license email.

If you only want a different license email and can still receive mail at the old address, you don't need to do anything: your existing TestFlight access keeps working.

### How do I change the bound Apple ID? (Or if operation errors cause the invitation code to become invalid)

You can opt-out in the management page mentioned above, wait about 90 days, and then rejoin. If you rejoin earlier, the invitation can only be accepted with the same Apple ID as before.

### How to cancel TestFlight email notifications and push notifications

All TestFlight-related push notifications and emails are sent by Apple. To cancel emails or push notifications, you need to operate within the TestFlight App.