I use the app called EAR. It's free and everyone has it. You simply open up the EAR app and adjust your amps until your system sounds good and then your done.
No but seriously I have never heard of such a App.
JL audio has a App with a DB meter A SPL meter and a Spectrum Analizer I could see the Spectrum Analizer working or helping out if your were trying to set your system up for A SQ comp but not a real life set up