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

https://itunes.apple.com/cl/app/arte-ar/id1266075849?mt=8

one of the images with problems

thanks for your time :slight_smile: