Paper-based chemical sensing devices, inspired by human sensory systems, offer a cost-effective and environmentally friendly approach to the detection of various analytes. These devices use cellulose-based paper as a substrate, exploiting its porosity and capillary action to enable rapid and accurate detection. The integration of functionalized chemical sensors, such as conductive polymers, metal nanoparticles, and enzymes, allows the selective detection of specific compounds. The electronic nose component of the device uses both electrical and optical sensors to mimic the olfactory system, detecting volatile organic compounds (VOCs) through changes in electrical resistance, capacitance, or optical properties (such as absorbance or fluorescence). Similarly, the electronic tongue (e-tongue) incorporates taste sensor arrays, including optical sensors, to mimic the sense of taste, using potentiometric, voltametric, impedance, or optical measurements. The e-tongue device is used to measure the samples in the liquid phase. The applications of these paper-based sensors are diverse, including food quality monitoring, environmental sensing, and medical diagnostics. The incorporation of optical sensing techniques increases the sensitivity and specificity of the devices, allowing for a wider range of detectable analytes. The simplicity and versatility of paper-based sensors make them a promising tool for on-site and real-time analysis. The low cost of materials and ease of fabrication further enhance their potential for widespread use in resource-limited settings.