Image based lighting is a common technique for creating realistic lighting in 3D scenes, and it usually relies on HDRIs shot with a DSLR across multiple exposures, then combined into a 32-bit file. That process can take hours per HDRI. Easy Environment Lighting takes a different route in Blender: capture an environment map with your phone, then boost its contrast with the shader, a process that takes about five minutes.
The workflow uses the Photosphere app to create an environment map on your phone, which produces a low-contrast image. You then load that image into the included node setup, and it boosts the contrast so you get lighting out of a map shot with your phone. The documentation covers both capturing a map with your phone and using the shader.
The package includes the shader, which makes every image an HDRI, plus five environment maps at 47 megapixel resolution. The maps are low on memory, roughly 1/16th compared to a 32-bit image of the same size. It targets Cycles and Blender 2.6x and 2.7x, and is offered under a royalty-free license.