A system and/or method for sensing the presence of moisture (e.g., rain) and/or other material(s) on a window such as a vehicle window (e.g., vehicle windshield, sunroof or backlite). In certain example embodiments, a plurality of sensing capacitors are supported by a window such as a vehicle windshield, the capacitors each having a different field and/or pattern. A sensing circuit outputs an analog signal that is based on and/or related to the capacitances of one or more of the sensing capacitors. In certain example embodiments, a flexible printed circuit board (PCB) mountable in or on a vehicle window is provided. First and second sensing circuits are formed on opposing sides of the flexible PCB, with each said sensing circuit comprising a plurality of different fractal structures. A ground plane is located between the first and second sensing circuits, with the ground plane being arranged so as to decouple the first and second capacitor arrays and to shield the first capacitor array from fields emanating from the second capacitor array and vice versa. The electronic device is configured to detect moisture on an exterior surface of the vehicle window, humidity on an interior surface of the vehicle window, and EMI.