This case series elucidates pathological signs for diagnosis in two patients with Dementia. The first case highlights the term 'Smartphone sign', a novel psychopathology uncovered based on the existing 'TV sign', a rare type of delusional misidentification syndrome (DMS). The second case had symptoms consistent with the 'TV sign'. The possible underlying cause of these signs was hypothesized based on psychopathology, brain region, sensory system, cognition, and environmental factors. Moreover, the treatment outcome in terms of cognition and behavior on low doses of Risperidone and Escitalopram shows promising results and paves the way for the treatment of other DMS.