> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mobster.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Untrusted Developer

> iOS shows this when the developer that signed the app isn't trusted on the iPhone yet. Trust it in Settings › General › VPN & Device Management, with the phone online.

iOS shows this alert when you open an app that Xcode installed with your Apple Account, such as WebDriverAgent's runner:

```text theme={"theme":"css-variables"}
Untrusted Developer
Your device management settings do not allow using apps from developer "Apple Development: <your Apple Account> (<team id>)" on this iPhone. You can allow using these apps in Settings.
```

Reports quote this wording from iOS 15 (2021) to October 2026. Older iOS versions said the developer `has not been trusted on this iPhone`.

On the Mac, `xcodebuild` and `xcrun devicectl device process launch` report:

```text theme={"theme":"css-variables"}
Unable to launch <bundle id> because it has an invalid code signature, inadequate entitlements or its profile has not been explicitly trusted by the user.
```

`devicectl` wraps that line in `ERROR: The application failed to launch. (com.apple.dt.CoreDeviceError error 10002 (0x2712))` and `The request was denied by service delegate (SBMainWorkspace) for reason: Security`. Xcode's own alert calls it `Developer App Certificate is not trusted`.

When the helper hits it, Mobster for Mac shows `Trust the helper app on your iPhone: open Settings › General › VPN & Device Management`, with a picture of that screen. Within 10 minutes of the failed start, `mobster doctor` prints a `✗` beside **Phone connection** with `doesn't trust the helper app yet` and the same steps.

## Why it happens

The developer that signed the app isn't trusted on this iPhone yet. Appium's provisioning guide describes it for free Apple Accounts, which Xcode lists as a Personal Team. A report on Apple's forums (2021) shows it for a paid team's build too. Mobster can't trust the developer for you: only you can, in Settings on the phone.

The `xcodebuild` line has a second cause. When a free account's signature expires after 7 days, iOS refuses the app with the same sentence. Mobster checks the signature's date before it reads the sentence, so it tells the two apart.

## Fix

1. Tap **Cancel** on the alert.
2. Connect the iPhone to the internet. iOS checks the developer's certificate with Apple when you trust it.
3. Open **Settings › General › VPN & Device Management**.
4. Under **Developer App**, tap the entry with your Apple Account.
5. Trust the developer, then confirm. In Appium's provisioning guide the first button reads **Trust** with your Apple Account after it, and the second **Allow**.
6. Open the app again. For the helper, choose **Try again** in Mobster for Mac, or wait: Mobster starts it again by itself.

If iOS says `An internet connection is required to verify trust of the developer`, connect the iPhone to Wi-Fi and try again.

If the developer is listed with no **Trust** button, a report on Apple's forums for iOS 15 fixed it with a new certificate: **Xcode › Settings › Accounts › Manage Certificates › + › Apple Development**, then install the app again.

If the developer is already trusted, the signature may have expired: see [the runner's signature expired](https://docs.mobster.dev/troubleshooting.md#runner-expired).

## Check it worked

The app opens. For a regular app, `xcrun devicectl device process launch --device <UDID> <bundle id>` launches it with no `Security` error. For the helper, `mobster doctor` prints a `✓` beside **Phone connection**. See also [Invalid code signature](https://docs.mobster.dev/troubleshooting/invalid-code-signature.md).

Checked 5 Nov 2026 against Mobster 0.4.0. Back to [Troubleshooting](https://docs.mobster.dev/troubleshooting.md#iphone).


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.