How to simulate low fps on iOS device?

Question

I want to simulate how the old CRT screens work on my iPhone. I need any ideas.

EDITED:

I'm interesting in 29.97Hz

Answer 1

You can't simulate the actual flicker of a CRT on an LCD display. However, if you're looking to make a scene or portion of your game look like it's on a TV, you can do any of a few tricks.

TV shows are typically 24 Hz. DVD's go up to 29.97 Hz. A little known fact is that Disney, like many animation studios, only animates at 12 Hz and shows each frame twice to achieve the 24 Hz. This means that to get the stutter associate with animated films, 12-15 Hz is your goal.

As already stated, LCD, LED, or Plasma displays are solid pictures, not strobed as CRTs are. You need to add strobing. I've found adding a single white frame every 3-4 frames add the desired effect. Typical game frame rates are 60 Hz, so a single frame lasts for 1/60 sec (or 16.7 ms). If every 4th frame is white, you get a flash simulating a refresh rate of about 15 Hz.

Answer 2

you cannot simulator the properties of CRT screens that make them flicker when recorded using a camcorder on a non-refresh recording frequency, LCD displays don't update the screen partially like CRTs do.