Anthropogenic emissions from traffic and industrial activities and their impact on air quality are a major concern in urban areas. The concentration of the air pollutants from these sources is typically measured with stationary air quality monitors, which are often limited in number. In addition, these stationary measurements often prove inadequate in representing the emission scenarios of the entire city due to the large spatial variability of these pollutants in urban environments. On the other hand, using specialized mobile monitoring techniques helps to evaluate air quality by better capturing spatial variability of pollutants in different micro-environments throughout the city. This study focuses on mobile monitoring of ambient concentrations of HCHO and optical properties of PM2.5 (particulate matter ≤ 2.5 μm) in different locations in Houston. The mobile measurements were conducted during the Mobile and OFFshore Measurements (MOFFS), in September 2023. The measurements to be discussed include Picarro for measuring HCHO and Methane, the Tricolor Absorption Photometer (TAP) for measuring aerosol absorption coefficient, and the Nephelometer for measuring scattering coefficient. Mobile measurements in this study will be used for the characterization of air quality in industrial areas, urban areas, and urban backgrounds, with the long-term goal of improving the spatial resolution of urban atmospheric chemistry and exposure assessment.