The Question/Answer option adds a [Q/A] button to the main screen.
Pressing this button will show 'Yes' and 'No' graphics that brighten according to the magnetic force on the left or right side of you phone.
Using this, you can ask questions of any entities, and have them light up the 'Yes' or 'No' indicators.
Pressing the [Q/A] button will toggle between the Q/A Mode and the regular Entity Sensor screen.
Each press of the [==>] start button resets the starting (Zero) value for the X sensor.

Don't move the phone while using Q/A mode, or the values won't be accurate.
 
Here is the main screen with the Question/Answer mode activated: