Black loading screen on iPhone 13 after prolonged app usage

Expressing or conveying visual experiences effectively through these forums may be challenging. The underlying visual issue on your iPhone cannot be accurately diagnosed online. Factors such as your iPhone's specific settings, visual defects, and potential hardware problems cannot be assessed through this method. For more personalized and in-depth assistance, I recommend securing a Genius Bar Reservation and exploring the various support options provided by Apple.

Get a Genius Bar Reservation and Apple Support Options - Apple

When you encounter issues with your Apple devices, the Genius Bar at Apple Retail Stores is the go-to place for expert assistance. The Genius Bar is staffed by knowledgeable Apple employees, often referred to as "Geniuses," who can diagnose and resolve a wide range of hardware and software-related problems. To ensure personalized attention and a convenient visit, Apple provides the option to schedule a Genius Bar Reservation.

Contact Genius Bar.

Manage Reservations - My Reservations - Apple

1. Make sure you have the latest updates installed.
   1. Update Over-the-Air (OTA) —> Update your iPhone or iPad - Apple Support (IN)
   2. Update using iTunes/Finder —> Update your iPhone, iPad, or iPod touch - Apple Support (IN)
2. Follow the Apple article to resolve the issue --> If your iPhone, iPad, or iPod touch won't turn on or is frozen ...
3. If not resolved; please follow the steps in the following link for support with this issue: If your iOS device restarts or displays the Apple logo or a spinning gear unexpectedly
4. You still see a black screen after charging, force restarting, following the steps in this article.
   1. You see a black screen, but you can hear alerts, sounds, and vibrations.
   2. The screen remains black, but the device chirps when you unmute it and connect it to power.
   3. Your screen is on, but it doesn't respond when you tap, slide, or try other gestures. 
   4. You can't force your device to restart because a button is broken or stuck.
   5. Your device is stuck on the Apple logo, displays a solid color, or isn't recognized in iTunes.
   6. Contact Apple Support to set up service if you have any of the above issues:
5. Please follow the steps in the following Apple Video for support with this issue:

If none of the above steps resolve the issue, it is recommended to reach out to Apple Support or visit an authorized service center for further assistance. They can provide specific guidance based on your device model and iOS version.