FPS drop on iPhone 14 Pro

• Screen Recording or Video Recording or any a Social Networking app recording is not clear from your Post
• Is it the Camera App or any third-app being used for recording is also not clear from your post
• Guded Access lock an App which is the device lock on to is also not clear.

With the limited information that you have provided I am making wild guesses here...

1. Enabling features like Guided Access and recording video can put additional strain on the device's hardware. When you turn on Guided Access, your iPhone is essentially locking down the user interface so that you can't interact with it outside of the app you're using which can lead to FPS drop.
2. Recording a video can also put a strain on your iPhone's memory. If your iPhone is running low on memory, it may have to throttle the CPU and GPU in order to free up some resources.
3. When you turn on Guided Access, the device restricts touch inputs to a specific app or feature, which may require additional processing power. Recording video, especially at high resolutions or frame rates, requires continuous encoding and storage of data, adding to the processing overhead.
4. Extended usage of demanding features can lead to increased heat generation, causing the device to activate thermal throttling. This is a mechanism to prevent overheating by reducing the performance of the CPU and GPU, which can lead to lower FPS during resource-intensive tasks.
5. Background processes running on the device can consume system resources, affecting the overall performance and causing FPS drops during resource-intensive tasks.