This script projects the boundaries of the FOV of a camera and shows gizmos so you can see what is visible and what isn't. You can put many scripts on the same camera, each with a different aspect ratio so it is great for seeing what phones, tablets and different PC screen sizes will see.
Show the frustrum and see where it intersects on your colliders

Put many scripts on the same camera to give you a great idea of what all the different player resolutions will see

