Online urban mapping executed by its inhabitants could contribute significantly to creating better evidence-based urban policies. The reason behind is that the inhabitants as daily users of the city identify their needs in the city most accurately. The municipality should take their opinions into consideration as they are its only clients. The main aim of this article is to present online mapping by inhabitants and demonstrate under what circumstances this kind of mapping could be beneficial for the municipality. For this purpose the article uses an example of the municipality Capital City – Bratislava, the area of the Old Town, and data from the portal odkazprestarostu.sk, which is an online mapping portal available for inhabitants and municipalities free of charge.