This is not a light meter – Incident Light Meter Review

Unlike other light meter apps, this app does not take any light measurements. It should be called a calculator not a reader. You have to metering in your camera. Then you enter two numbers into the app (the two shutter speeds) and it calculates a weighted average of your two numbers. That's all the app does. It's not much bang for the buck! The instructions on metering provided by the app aren't anything you couldn't find easily and better for free on the web. The app is just a plug for the author's photography training.
Review by v700 on Incident Light Meter.