It's not so effect now, but years ago, I had good luck using a cellphone camera as a crude light meter for a greenscreen. When your sensor only gives you 3 or 4 stops of range, subtle lighting irregularities really stand out.
I'd scan the scene with my phone camera, looking for hot spots or shadows my eyes missed.
Now that smartphones have his the scene and cameras have gotten a lot better, this technique isn't nearly as effective.
Since the MacBook Pro is one of the best Windows laptops out there, being limited to Windows is an issue only for those who run a single OS.
This software is going to be huge for low budget TV shows, and especially for ultra low budget web series. Can't wait to play around with this.