The increasing demand for healthy and convenient food options has led to a rise in the use of technology for analyzing the nutritional content of packed foods. In this comprehensive review, we explore the application of smart phone camera/computer vision and machine learning in this domain. We delve into the challenges faced in analyzing nutritional content and the limitations of traditional methods. The potential benefits of using smart phone cameras/computer vision and machine learning are discussed, including the ease of use and accessibility to a wide range of consumers. We examine various studies that have implemented these technologies for nutritional analysis and evaluate their effectiveness. The potential for future developments and improvements in the field is also considered. By leveraging the power of technology, we can gain deeper insights into the nutritional content of packed foods, leading to more informed consumer choices and improved public health outcomes. This review aims to provide a comprehensive overview of the current state of the art and stimulate further research in this exciting and rapidly evolving field.