3D bad performance in iOS for augmented reality

Hi! I have developed an augmented reality applicacion (vuforia 6, unity 2017) for iOS/Androis. In android the behavior is fluid for the 3D model but in iOS de fps go down to about 5 or 3 FPS. I tried to simplify the shaders and use less effects and lights but nothing.

the android version I tested on a nexus 5 and a huawei p) so I´m surprised that an iPAD 2016 and an iPhone 6 worked bad. Do you have any similar experience? dows it have anything to do with the unity graphics engine?

the aplication is “arte AR” and is free in appstore


one of the images with problems

thanks for your time :slight_smile: