Comprehensive monitoring of air pollution data is necessary for policy makers to develop air pollution control strategies. Ozone and nitrogen oxides are key sources of air pollution in urban areas and need to be studied in order to understand the intricate processes through which they accumulate, disperse, transform and removed. Low cost, mobile electrochemical sensors are installed for a period of six months in three characteristically varied urban locations (Maximillianstrase, Hofgarten and Spinnerei) in Bayreuth to analyse seasonal and diurnal variations of NO, NO2 and O3 levels. A seasonal trend with higher ozone and lower NOx (NO+ NO2) concentrations during spring and summer, and low ozone and high NOx concentrations during winter is observed in all three stations. An atypical trend for NOx and O3 levels is observed during the coronavirus lockdown period (21st March’ 2020 – 30th March’ 2020). The electrochemical sensors are calibrated and evaluated with varying temperature (10, 24 and 30° C) and humidity conditions (44% and 75% RH). A strong linear relationship between the recorded voltages and target concentrations of gases are observed over a wide range of concentrations.