Good, but FFT is better (I guess)
I was at work (Im a live sound engineer) and we were discussing speaker phase, when I said "They should make an app so you could test spkrs with iPhone." It didnt take long before I found all the Studio 6 products. I now have SpeakerPop, GEN, SPL, & RTA. They all work wonderfully.
That said, I was a little disappointed to learn about FFT. Its not made too clear in the descriptions, but FFT is basically a more accurate & detailed version of RTA. I wish Id bought FFT, since I want the most accurate thing availible. However, Id already purchased RTA, & because of App Store rules, I cant trade it in towards FFT.
If youre going to spend $10 on an app, you are probably going to use it for work like me, so splurge & get the $20 FFT. I am debating it, my main hangup is that Ive already spent $10 on the RTA app.
Ahavill about
RTA