Lux Meter - light measurement tool for measuring lumens, foot candles, lx and light temperature 4+

I was looking for an app that could help me match lighting sources. When replacing burned out sources, it's important to match the color temp of the replacement with other existing sources. So I downloaded this app in hopes that it would be a handy tool. Not so much.
I tested the app with two banks of fluorescent tubes, each was clearly either daylight or a much warmer color. If I could upload a photo, you would easily see the difference. Yet this app rated them at essentially the same degrees Kelvin, 5150 (actual: 7 degrees different).
Maybe the eye and camera is very sensitive to color shifts and consequently it's too much to ask of an inexpensive app to resolve the difference. But using this app to chose replacement bulbs in a home or office would give unreliable results in matching sources.

This works well enough to use if you don't have any lux meters in hand. I currently have the pocket sized ex tech low range meter. This is my go to meter. Unfortunately the phones meter fluctuates a little too much for me and is usually a little off with the measurements. I'll try using this at night for a parking lot we are working on to help us with installing light posts. Also, when I click the info button it has an 'x' to go back. Every time I click the info button to land on that page the 'x' moves location. The text should also take up the width of the phone and not just 2/3 of it. Currently running on an iPhone 6 plus.

We cannot generate consistent readings with this App. One of our consulting engineers placed a professional meter next to the App and got widely different readings. We didn't expect the App to be super accurate but hoped that it would give our designers "ball park" readings. The reality is it appears to be no where near close. The same App on different iPhones generates different readings in the same location. Does this camera generate readings from the front or back camera? Do you place it on the lit surface or focus the camera on the surface? The documentation is lacking so it hard to know.