I have been a Audio Engineer, Running live sound for bands, for 13 years. I have seen some really good analysing equipment in my day. Some ranging up to 1,000 dollars for one unit. But this app is AMAZING. It is very accurate in reading dbs or loudness of a room and sound system. It has a really good range on it also. The frequency response is really solid also. When I start to get feedback at a show its right on with what frequency is giving me trouble. If you are a novice Sound guy at a Church or an expert that is on Tour i would recommend this highly. And you can't bet the Price of FREE either.