ARCore is Google's software development kit for building augmented reality apps on Android. ARCore handles computer vision: detecting planes in the physical world, estimating light and motion, anchoring 3D objects to real space. Developers build the AR experience (3D models, interactions) using ARCore's APIs in Kotlin, Java, or via Unity. ARCore apps can detect surfaces (walls, tables), recognize objects and images, place persistent 3D content, and sync anchors between users via cloud.