Together with technological innovations and the development of a digital society, PPGIS approaches have been rapidly growing popular in the last years, in Poland’s local administration. Local governments take significant interest in online tools; however the principles of public participation, which, in fact, should also be applied to e-consultations, are still missing. One of the assumed roles of PPGIS is to support public participation—not just in terms of the number of stakeholders, but especially in terms of the impact on decision making. The present paper discusses the results of investigations into two decision-making processes, regarding local spatial planning in the Poznań agglomeration, Poland, conducted in 2015–2021. Its aim is to verify the hypothesis that the use of PPGIS facilitates more meaningful involvement of citizens in spatial planning. As a result of the case study analysis, in-depth interviews with local authorities and officials, and analysis of the planning documents and the role of PPGIS in public participation in decision making, was investigated. It was shown that in both processes there was no direct participation of society in decision making. However, the use of PPGIS, according to local authorities, had implications in the context of the wider process of local governance.