Owlet 1.7.1 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The software relates to Design & Photo Tools. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe. This software for Mac OS X was originally designed by AppsforLife.
From the developer:
Owlet is a standalone, unbiased, physically-based raytracing renderer. The app loads 3D models in many common formats, allows you to compose the scene and setup materials, and then renders resulting images using our state-of-the-art raytracing engine.
You may want to check out more software for Mac, such as Interiors, 4D Runtime Interpreted or Geo3D, which might be related to Owlet.