In many European cities, public spaces are transformed towards more livable areas that promote active mobility and reduce car traffic. A great variety of approaches aims to evaluate individual projects. Given the diversity in methods, indicators used, sample sizes, observation periods as well as spatial expansions of the area under investigation, it is difficult to merge results from different case studies. Consequently, deriving general trends is challenging. We set up a methodology using big data from mobile phones to assess the effect on pedestrian frequency. This indicator works as proxy for the effect of street redistribution and traffic calming. We test the method by evaluating the development over time and space in three district centers from 2019 to 2023 in Berlin, Germany. One of these streets has been redesigned in favor of active mobility and quality of stay while the other two remain unchanged and are used to set a context. Results show a much higher increase in visits in the street that has been redesigned. Added value of this contribution is the development of a comparable and transferable evaluation method that is able to assess the impacts of transformations in public areas.