'Trust This Computer' alert on iPhone, iPad, or iPod touch
When you connect your iPhone, iPad, or iPod touch to a new computer or another device attempting to access the files of your iOS device, you'll see an alert asking you to verify that you trust the connected device. If you tap Trust, you'll allow this device to access files stored on your iOS device.
If your iOS device is passcode locked, you need to unlock the device before you'll see the alert.
To trust a computer:
- Connect the computer or other device to your iOS device.
- If your iOS device is locked with a passcode, unlock it.
- Tap Trust.
- If you're about to sync the device with iTunes, click Accept.
The trusted computer or device can access the files and settings of your iOS device. A trusted computer can sync with your iOS device, import photos, access movies and videos, contacts, and other such content, until you disconnect. The data stored on your iOS device isn't exposed before you enter your passcode (if enabled) and choose to trust the connected computer or device.
If you choose not to trust the connected computer, you can charge your device, but the connected computer won't be able to access any content on your device.
If you tap Trust, the computer will be trusted until you untrust all computers or you erase the device. If you tap Don't Trust, you'll see this alert each time you connect your device to that computer.
If you're using iOS 8 or later: To untrust all computers, tap Settings > General > Reset > Reset Location & Privacy. This will also reset your location and privacy settings. You can also untrust all computers by tapping Settings > General > Reset > Reset Network Settings. This will also reset your network settings.