Not calibrated. Missing features. You can find better.
This program has limited features, and is quite expensive.
1. It is NOT calibrated for the iPhone microphone. To quote a response from their tech support:
"Pocket RTA uses fast fourier to analyse an input signal so it's frequency
detection is incredibly accurate, however the quality of the internal
microphone is far from perfect, so accurate dB readings at across the entire
frequency spectrum are not its forte. In particular low frequencies below
100Hz and high frequencies over 12-13KHz are not so accurate.
We do allow you to calibrate yourself if you have the required test
equipment, but don't apply any pre-determined calibration."
Right there I wish I could get a refund! Other programs are pre-calibrated for each iPhone model.
2. It lets you output a tone, or "noise", but the tone requires you to key in a frequency. This makes it impossible to sweep the tone up and down. I wanted to use it to test speakers, but I can't do that without the ability to sweep the tone. Again a quote from tech support:
"Unfortunately Pocket RTA doesn't have the ability to perform sweep tones at
present, but might be something we will add in future updates."
3. The price is about 3x too high. It's much higher than others that work better.
I gave this app two stars instead of one because they actually responded to my questions. Unfortunately I can't use it, and wasted about $30.