Correcting 3D model error in Ionic mobile app -- 2

We have working on a Ionic Project showcasing a 3D human model on Ionic mobile app. But it is behaving differently on different devices. i.e. on some it is working fine, on some textures are not showing and on some app is crashing. We want someone to resolve this for us so that it works perfectly and uniformly on all devices - iPad, iPhone - all versions, android phones - all versions, any RAM, any processor etc.