The article presents the results of a spectroscopic EPR study of smartphone touchscreens after their exposure to ionizing radiation. It is shown that smartphone glass samples may have their own technology-related EPR signals, which may cause systematic errors in the results of dose reconstruction by the EPR method. Several types of radiation EPR signals have been identified, as well as variations in the radiation sensitivity of glasses. A linear response of the EPR signal to irradiation in the range of 0-1 kGy was detected.