The app I use is android based so I doubt it'll work on your i-pad.
It was interesting walking around while the Champ was running and seeing just how far away I needed to be for the db's to drop to 50, then 40 and finally in the 30's. Now I know it would have to be a pretty spread out CG to make it's use acceptable. Since I've never been in a CG with that kind of distance between sites, I'll continue on as I have with the solar.
BTW It took until I was far enough away for the noise level to drop to 40 db and below before I could hear a near by bird sing.