Fabulous, free, AR making tool.
Create AR audio walks with this tool.
A library to be used with AR/VR tool A-Frame that provides the ability to import 3D panorama frames.
A desktop tool with which you can create 3D Augmented Reality apps that do face tracking and other cool AR features. You can create interactive patches using a visual flow language or code in Javascript.
Tools to help you create Augmented experiences.
An app with which to make AR (Mac)
Not free, but you can use it developer mode to create compelling image-based Augmented Reality experiences. Great tool
A huges collection of articles about AR and VR projects