A device includes camera hardware configured to capture image data associated with an output signal area of a biological chromatographic test strip, and processing circuitry configured to determine, based on the image data, respective intensities of a control line displayed in the output signal area of the biological chromatographic test strip, a hook line displayed in the output signal area of the biological chromatographic test strip, and a test line displayed in the output signal area of the biological chromatographic test strip. The processing circuitry is configured to determine a relative intensity between the test line and at least one of the hook line or control line using the respective intensities, and to detect, based on the relative intensity, a presence of a target analyte in a test sample submitted via the biological chromatographic test strip.