Infographic of pH Watch (IMAGE) National University of Singapore Caption By integrating the NUS team's custom-made pH sensor (middle) and pH sensing algorithm into existing fitness trackers or smartwatches which already have a built-in pulse oximeter, the pH Watch can simultaneously monitor the pH value of a user's sweat, along with heart rate and blood oxygen saturation values in real-time, with about 90 per cent accuracy. Credit National University of Singapore Usage Restrictions Please credit accordingly License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.