In parallel with the developments in information and communication technologies, traditional participation in urban planning processes is gradually evolving into e- participation applications. For the effective use of e-participation applications, it is important to evaluate the effectiveness and quality of the applications in terms of participation mechanisms, design, interaction, structure, transparency, and security of processes. The aim of the study is to examine Istanbul Senin application in terms of e-participation, to investigate the use of this application by the citizens and to offer suggestions for its improvement.The study seeks answers to the questions of what the positive and negative aspects of the Istanbul Senin application are in the context of e-participation and how it is used by citizens. The study was designed in two stages. First, Istanbul Senin application was analyzed in line with the criteria for evaluation of e-participation platforms. Second, a survey was conducted to examine the use of this application. The sample group was determined on a voluntary basis and a sample of 100 participants was determined within a reasonable margin of error (10%), taking time and cost into account. Accordingly, issues such as informing and raising awareness of the citizens about the importance of participatory processes, increasing the familiarity of the application, improving the design and increasing the ease of use, improving the way of interaction have been emphasized for the Istanbul Senin application.