To perform a physical performance test is a good way to keep track of one’s health and can be beneficial to find evidence of deviations in the body. This thesis focuses on the development of a mobile-based heart rate algorithm that can be used with the Queens College Step Test, on the behalf of Mobistudy. Mobistudy wants to include such a test in their mobile application which aims to become a tool for researchers to use to gather data. The algorithm uses the mobile device’s camera to collect data from the user’s finger and uses that data to calculate the heart rate. The algorithm was first tested with data collected during the development and the results has an average error of less than 5% and a standard deviation of less than 3%. Two participants between the age of 20-25 performed three sets each of the Queens College Step Test and the results showed that the algorithm was accurate in its estimation of the heart rate after the test.