The public health crisis caused by the current COVID-19 pandemic ('the COVID19 crisis') forces the European Union and the Member States to face an unprecedented challenge which has put at risk not only their health care systems, the normal development of administrative action or its economic stability, but also the set of values and way of life that make up the concept of European citizenship. In this context, the technological development resulting from the profound processes of digitization and datification of society that we are witnessing in recent years, is presented as a definite alternative to inform citizens and assist relevant public authorities in their efforts to contain the spread of the virus. In addition, they can be a valuable tool to reverse the isolation based on data models strategies that point to the potential effects of relaxing social distancing measures. However, the implementation of some of these measures raises questions from the point of view of several fundamental rights and freedoms guaranteed in the legal system, especially the right to privacy and the right to protection of personal data. The purpose of this study is to clarify, on the basis of the law, the main questions surrounding the use of technology in times of disaster, helping to clarify the difficult balance between technological development and the guarantee of citizen's fundamental rights, paying particular attention to the protection of personal data.