A sensor patch comprising: a perspiration volume sensing channel including a first colorimetric material, the first colorimetric material configured to change color in response to exposure to perspiration; a perspiration component sensing chamber including a second colorimetric material, the second colorimetric material configured to change color in response to exposure to a biochemical component in the perspiration; a channel inlet port in a bottom surface of the sensor patch and in fluid communication with the perspiration volume sensing channel, the channel inlet port being configured to provide a path for the perspiration to enter into the perspiration volume sensing channel; a chamber inlet port in the bottom surface of the sensor patch and in fluid communication with the perspiration component sensing chamber, the chamber inlet port being configured to provide a path for the perspiration to enter into the perspiration component sensing chamber; a channel vent port in a top surface of the sensor patch, opposite from the bottom surface, and in fluid communication with the perspiration volume sensing channel, the channel vent port being configured to release backpressure out of a top surface of the sensor patch as the perspiration fills the perspiration volume sensing channel; a chamber vent port in the top surface of the sensor patch, opposite from the bottom surface, and in fluid communication with the perspiration component sensing chamber, the chamber vent port being configured to release backpressure out of the top surface of the sensor patch as the perspiration fills the perspiration component sensing chamber; and a near field communication circuit and a near field communication antenna. a perspiration volume sensing channel including a first colorimetric material, the first colorimetric material configured to change color in response to exposure to perspiration; a perspiration component sensing chamber including a second colorimetric material, the second colorimetric material configured to change color in response to exposure to a biochemical component in the perspiration; a channel inlet port in a bottom surface of the sensor patch and in fluid communication with the perspiration volume sensing channel, the channel inlet port being configured to provide a path for the perspiration to enter into the perspiration volume sensing channel; a chamber inlet port in the bottom surface of the sensor patch and in fluid communication with the perspiration component sensing chamber, the chamber inlet port being configured to provide a path for the perspiration to enter into the perspiration component sensing chamber; a channel vent port in a top surface of the sensor patch, opposite from the bottom surface, and in fluid communication with the perspiration volume sensing channel, the channel vent port being configured to release backpressure out of a top surface of the sensor patch as the perspiration fills the perspiration volume sensing channel; a chamber vent port in the top surface of the sensor patch, opposite from the bottom surface, and in fluid communication with the perspiration component sensing chamber, the chamber vent port being configured to release backpressure out of the top surface of the sensor patch as the perspiration fills the perspiration component sensing chamber; and a near field communication circuit and a near field communication antenna. <EOS>