Audio Function Generator 4+

So much handier than a bench box, the kind of thing I trained on. Developer responds to queries too.
Now updated to Pro: well worthwhile, much more capability, varieties of white noise, multiple tones, pulse generator. Now using to put amps to test, look for intermodulation, assess compressor behaviour... Learning a lot as well, exploring capabilities. What a clever developer!

This app does everything you might want for stereo audio applications. I identified a faulty capacitor in a LS crossover using its white noise output plus a spectrum analyser on a smart phone.
On an iPad mini there is a second or so delay on the controls. The screen frequency readout on a swept sinewave lags well behind the actual audio frequency.

April 2018: Just measuring some new speakers. The steady coloured noise is fine. The swept frequency has two problems using it over Bluetooth, which puts in 3-4 seconds delay. The initial bit of sweep may be lost somehow I think.
Also the sweep is linear with frequency increasing >200 Hz/sec or so. This means the lower end <1khz is swept much too fast and the top end takes forever. Would a log rate work better?
Also having probs with the phase shift controls. Don’t do what I expected.
May 2018: I have got my oscilloscope connected now and it confirms that the phase shift controls are not accurate. Sliding the top one to 180 deg. only gives a 45 deg shift. If I then set the bottom one to -90 deg I get a 90 deg approx relative shift and a bit more if it’s set to -180 deg. Could the Bluetooth be doing this?

The features of this application are great! Intuitively designed with predefined functions providing spectral audio for automated frequency generation make this app’ superb. Volume adjustment control’ can be improved. Sinusoidal repetitions via frequency alteration with the burst upgrade! Surely cannot find a better represented, easy to use audio frequency range generator on the App Store.