AR Foundation allows you to work with augmented reality platforms in a multi-platform way within Unity.
RealityCapture is a photogrammetry software that allows users to create 3D models from photographs or laser scans.
Metahsape is a low-cost software that performs photogrammetric processing of digital images and generates 3D models.
Apple's ARKit provides a way to situate stories in the viewer's real environment using augmented reality on Apple devices.
Aero from Adobe is an app for viewing, building, and sharing immersive and interactive AR experiences.