Photoplethysmography (PPG) is a simple optical measurement technique used for blood pressure and heart rate monitoring. PPG signal and its derivative contain important health-related data which is used for the detection and diagnosis of cardiovascular diseases. High blood pressure is a cause for various physiological changes and leads to the cause of death throughout the world. Heart Rate Variability (HRV) is also an important factor for diagnosing cardiac disorders and to analysis the physiological conditions of human body. The growth of signal processing techniques, has opened the door for the development of cuff less and continuous monitoring of heart rate variability and blood pressure from the PPG signal. This article describes some of the current developments and challenges of PPG-based heart rate variability and blood pressure monitoring technologies.