Addressing urban heat and its impact on outdoor spaces and human well-being is critical for developing sustainable cities, particularly in the context of climate change, which is increasing both the frequency and severity of heatwaves. Traditional climate monitoring devices which are used to measure meteorological variables affecting thermal comfort are often expensive and require significant technical expertise to operate, limiting their accessibility. In response to these challenges, this study presents the development of UrbanMobiClim, a low-cost and user-oriented meteorological device, designed for mobile measurements of thermal comfort. Built on an Arduino platform microcontroller with low-cost sensors and guided by German standards for meteorological devices, UrbanMobiClim aims to empower urban planners and other stakeholders with accessible data to inform evidence-based urban adaptation strategies. UrbanMobiClim was statistically compared against two reputable high-end devices from the Dresden University of Technology's Chair of Meteorology and Arizona State University's Sensable Heatscapes and Digital Environments (SHaDE) lab, demonstrating its suitability for measuring thermal comfort in both stationary and mobile applications. This study presents the results of these comparisons, alongside a comprehensive technical framework for replicating the device. By establishing a baseline for future iterations, UrbanMobiClim contributes to the development of accessible, reliable, and easy-to-use tools that facilitate citizen science initiatives and support local stakeholders to make informed decisions for enhancing urban livability and sustainability.