This app DOES move the needle on the uT gauge when a specific part of your phone gets CLOSE to metal. NOTE: This app appears to be more sensitive to nearby metal if you take your iPhone out of its case (my Mophie case impedes sensitivity).
However, the metal must be VERY close to a specific area of the back of my iPhone in order to get a decent response from the meter.
For some inexplicable reason, the app displays a running graph display of the x, y, and z values of the ACCELEROMETERS during sensing.
I would have preferred to have NO accelerometer data displayed and instead see a running graph of micro-Tesla field strength over time.
Also, there appears to be no sensitivity setting nor is there a BEEP from the BASE METAL DETECTOR app to when the uT fluctuates indicating nearby metal.
Each of the above missing features are worth an additional star each. If those features are added, I wall award stars accordingly.