The 20th century brought about major social challenges related to civil and human rights, triggering changes in urban environments and gradually adjusting the spatial and functional performances of cities to the needs of all users. In this article, the concept of Universal Urban Design (i.e., “Design for All”) is regarded as a sustainable placemaking process which enables the higher accessibility and usability of cities for all people, regardless of their age or (dis)abilities. The pilot project “Creating Accessible Pedestrian Corridors by the Limitless GIS Application” conduced in Serbia from 2017 to 2019 by the Faculty of Architecture at the University of Belgrade and the Non-Governmental Organization (NGO) Limitless proposes an innovative approach to urban design. Based on information and communication technology (ICT) adaptation, it is focused on the alternative concept-design of buildings, provision of ICT-based infrastructure, socioeconomic integration of all users, and ultimately on overall urban sustainability. The main outcome of the project was the development of a Geographic Information System (GIS) android application and an e-platform for adaptive placemaking. The project also provides a set of accessibility criteria based on Universal Urban Design, criteria that enable the mapping of locations based on the type of use, a set of recommendations for identified problems, as well as a brief analysis of the latest technological solutions for overcoming detected physical barriers. The Limitless GIS android application differs from the existing ones since it primarily identifies two target groups: (1) people with disabilities who could upload necessary data by established criteria; and (2) employees in the public sector (city authorities and municipalities) in charge of planning alternative routes and setting priorities and investment costs based on the identified problems. Pilot results of the project have revealed that in the current Serbian practice, there is still a lack of planned, consistent and continuous movement routes in urban areas. Terrain configuration represents a serious limitation for people with disabilities, while lifting platforms are recognized as a better solution than ramps (both for paraplegics and quadriplegics), due to their higher efficiency and minimized spatial requirements. Therefore, the android application and e-platform presented in this article contribute to the detection of actual problems at the local level as well as to the overall improvement of planning/design practice in Serbian cities.