But until recently, the only way to build XR apps for Meta's headsets was with a game engine, such as Unity or Unreal, and Meta didn't provide any kind of UI framework for either. This is why many apps on your iPhone use the system design language, while every app on Quest, even the most basic experiences, the UI feels completely different, often custom-made by the developer or imported from the Unity Asset Store.

Meta has finally released a solution to this. It's called the Horizon OS UI Set, part of v69 of the Meta XR Interaction SDK for Unity, and provides Unity developers with the components to build interfaces that feel cohesive with Horizon OS.