What Is ARKit 2? iOS 12 Augmented Reality Features

ARKit 2 is Apple’s second-generation augmented reality (AR) platform introduced with iOS 12, offering developers advanced tools to create more immersive and interactive AR experiences. This article covers the core definition of ARKit 2 and details its key features, including multi-user shared experiences, persistent AR sessions, 3D object detection, and enhanced visual realism.

What Is ARKit 2?

Announced at Apple's Worldwide Developers Conference (WWDC) in 2018, ARKit 2 is a software development framework built into iOS 12. It allows developers to integrate virtual objects into the real world using the camera, processors, and motion sensors of compatible iPhones and iPads. ARKit 2 builds directly upon the foundation of the original ARKit, resolving earlier limitations regarding persistence, multiplayer capabilities, and real-world object recognition.

Key Capabilities Introduced in iOS 12

1. Shared Experiences (Multi-User AR)

Prior to ARKit 2, augmented reality on iOS was strictly a single-player experience. ARKit 2 introduced shared experiences, allowing multiple users on separate devices to view and interact with the same AR scene simultaneously from different vantage points. This enables collaborative design tools, shared educational presentations, and real-time multiplayer gaming. Spectator modes are also supported, allowing an observer to view another person's AR gameplay from a third-party perspective.

2. Persistent AR

Persistent tracking solves the problem of virtual objects disappearing once an app is closed. ARKit 2 allows apps to save the mapping of an environment alongside the positions of virtual objects. When a user reopens the app in the same physical space at a later time, the digital items reload in the exact locations where they were left.

3. 3D Object Detection and Tracking

While the first iteration of ARKit could recognize flat 2D surfaces and images (such as posters or book covers), ARKit 2 expands detection to complex three-dimensional objects. Developers can scan real-world items—such as toys, sculptures, or consumer products—and train apps to recognize them instantly in a room, anchoring interactive digital content around those specific objects.

4. Environment Texturing

To make digital assets blend naturally into the physical environment, ARKit 2 uses machine learning and camera data to generate environment textures. This feature estimates how the surrounding room looks and creates realistic reflections on virtual objects. Shiny or metallic virtual surfaces dynamically mirror the actual room around them, creating a more convincing optical illusion.

5. USDZ File Format and AR Quick Look

In partnership with Pixar, Apple introduced the open-source USDZ file format alongside ARKit 2. Optimized for sharing 3D content, USDZ files allow users to place and interact with 3D models directly within built-in iOS apps like Safari, Messages, Mail, and Files using a feature called AR Quick Look. This made AR accessible without requiring users to download dedicated third-party applications.

6. Enhanced Face Tracking

ARKit 2 improved facial tracking capabilities on devices equipped with the TrueDepth camera system. It introduced support for gaze tracking (detecting where the user’s eyes are looking) and tongue detection, adding greater realism to Animoji, Memoji, and third-party avatar applications.