Upgrade to iOS 13 gets stuck at the Apple logo and the horizontal progress bar

You may want to read If you can't update or restore your iPhone, iPad, or iPod touch on Apple's website. Essentially, You have two main options.

1. Force restart your iPhone

In other words, force your iPhone to reboot. How you do this will depend on your model of iPhone. Since you haven't specified this, refer to Force restart iPhone on Apple's website.

2. Put your iPhone into Recovery Mode

If you have an iPhone 8 or X follow these steps:

1. Connect your iPhone to a computer with a Lightning cable
2. Open iTunes on the computer
3. Press then release the volume up button on your iPhone
4. Immediately press then release the volume down button on your iPhone
5. Hold the side button, and keep holding it down till you see the Recovery Mode screen (this appears after the Apple logo

If you have an iPhone 7 follow these steps:

1. Connect your iPhone to a computer with a Lightning cable
2. Open iTunes on the computer
3. Press and hold both the side button and volume down button on your iPhone
4. Keep holding them down till you see the Recovery Mode screen (this appears after the Apple logo)

If you have an iPhone 6S follow these steps:

1. Connect your iPhone to a computer with a Lightning cable
2. Open iTunes on the computer
3. Press and hold both the Home and Lock button
4. Keep holding them down till you see the Recovery Mode screen (this appears after the Apple logo)