Handheld devices using an array of stainless steel electrodes located on an edge and/or back of the handheld devices for acquiring electrodermal activity are provided. The stainless steel electrode array may allow for the skin conductance level (SCL) or skin conductance response (SCR) on an individual to be measured and collected. The skin conductance signal may be related to sympathetic nervous system activity which is a major component of human emotion, known as arousal, or emotional intensity such as anxiety, stress, fear, or excited, etc.
