One of the problems that is becoming more prevelent these days is teh trend toward using Phones as investigative tools. It seems everywhere you turn these days someone has come up with something new for your phone. But how good are they?
In a couple words, not much. And the reason has less to do with the app than with your phone.
Start with cameras. While you certainly can take a picture with a phone you have to consider the optics available. A larger lens gathers more light and has a longer focal distance. How large is the lens in your camera compared with even a cheap point and shoot camera? And how far from the CCD sensor can it be considering the physical size of the camera?
Then we have various EMF sensing apps. What kind of sensor do you have in the phone? Answer is a very small one, probably single axis. And in a phone which is poorly shielded. So how dependable will the electronics be at providing the app with solid data?
Along the same line consider the frequency of the EMF. Radio, including wireless phones operate using RF which is in fact EMF. So the phone does have a good receiver for those frequencies. But the spectrum is very wide, and the RF portion used by phones is only a small part. So your phone has "ears", but they are very narrow in frequency coverage, limited to tht part of the spectrum used by the phone. And that is not the area we are concerned with as investigators anyway. Usually we try to block those frequencies. Of course, if an app can trigger on that region it might APPEAR to actually work. Result, they sell an app, and you get something which does nothing toward actually gathering the data you want. The field of paranormal research gets more garbage data and the myth builds which helps them sell more apps......
I am even seeing apps now that can turn your phone into a spectrum analyzer or oscilloscope. And with a bandwidth as narrow as a phone offers, that is about as worthless as it gets.
Audio recording is another area which is not really useful. The small mic in a phone is intended to pick up voice, and is built to get that with minimal outside interference from extraneous noise. So how, if it is supposed to minimize outside noise, is it good to get EVP? Besides, the design of a phone is intended to be handheld and carried about. Two things one should NEVER do when engaged in EVP research.
So with all these negatives related to the phone itself how does one expect some new app to be worth the time to install on the phone? Answer is, if you need an app, then buy the proper equipment to do this correctly. If you need a camera, buy a camera. If an EMF monitor, buy a meter or monitor. And for a recorder, buy a recorder with the capability of using decent external mics. Forget the phone apps, and use your phone to call your friends and schedule an investiagtion!