SignalSpy - Audio Oscilloscope, Frequency Spectrum Analyzer, and more

Useful app to take a closer look at a sound. I really like the spectrogram mode where you can see the evolution of peaks in the spectrum over time. Unfortunately the frequency scale is completely wrong - just feed it a pure sine wave of known frequency, and the peak appears at the wrong frequency (about 10x too low) Two years after I first reviewed this there is still lots of missing functionality: on screen stop/start, screen capture (without "screen shot"), ability to zoom / change scales, ability to add a cursor to read detailed information. Right now this is no more than a toy app, OK for exploring the sounds around you but no scientific instrument...

It's a shame this app is for sale. The spectrograph returns data that is off by a factor of 10. Play it a 440hz "A" and it reads out a bold line around 40hz. I can't read the exact measurement because the scale is useless. The RTA section is filled with noise, it looks like the FFT was not windowed at all, and the scale is linear. Annoying and useless. The oscilloscope seems cool, but there are not enough user controls to make it anything more than a fun waveform display. Complete waste. Please make the tweaks and give the users what they paid for.

It would ha been better if the x axis is adjustable for few seconds and also the ability to pause the plot.

You can't analyze anything with this app. There is no scales or units. It looks like in development mode and shouldn't cost any money yet.