3D model formats in ARKit / ARCore development

Question

I am a beginner at AR game development for both iOS and Android. I have the following questions:

1. What kinds of 3D model formats are supported by ARKit for i

Answer 1

ARKit doesn't care about model formats, because ARKit doesn't display 3D models (or anything else) itself.

ARKit provides information for use by a higher level rendering engine — Apple's SceneKit or SpriteKit, third-party Unreal or Unity plug-ins, or an engine you build yourself with Metal or OpenGL. The rendering engine is responsible for drawing the camera feed and overlaying 3D content to create AR illusions, and it uses the information ARKit provides in order to do so convincingly.

I don't know much about ARCore, but from all appearances it has the same role in the Android ecosystem — it's Unity, Unreal, or some other engine that handles the 3D models there, too.

So, questions like this are specific to whatever 3D engine you're using with ARKit/ARCore. SceneKit can handle DAE and OBJ directly, and a few more formats via Model I/O (see MDLAsset and SCNScene.init(mdlAsset:)). For Unreal, Unity, and whatever else you use with ARCore handle... see the documentation for those technologies.