This session discusses the past, today, and future of optical spectroscopy, especially for personal everyday applications. In contrast to other fast-moving IT technologies and industries, the optical spectroscopy technology and industry is decades behind due to lack of technology breakthrough from everyday applications perspective. Recently, multiple big markets show growing needs in spectral sensing capability and also require an ultra-compact size and at affordable cost. This session discusses and compares different technologies and solutions, and their strengths and potential issues. Lastly, the session attempts to forecast the future trends and market potentials of optical spectroscopy markets.