Key Features. Built-in GPSTrack your steps monitor your heart rate & more! Compatible with Android & i OS Smartphones Water resistant to 50 metres Lessen your stress The on-wrist EDA Scan app detects electrodermal activity which may indicate your body’s response to stress. You can use the Fitbit app to track trends over time reflect on your mood & try new mindfulness tools. Understanding stress is clearer with your daily Stress Management Score which comes with a helpful breakdown for Premium members. For the muscle that moves you Use the on-wrist ECG app to assess your heart for atrial fibrillation (AFib) a common heart rhythm irregularity. Plus stay informed with heart rate notifications when Sense detects that your heart rate is above or below your threshold Take health to the next degree Skin temperature tells a story about your body. Sense has an on-wrist skin temperature sensor to track your variation each night & show if it varies from your usual range so you can identify changes in your trends over time. A new way to see wellness Track Sp O2 the level of oxygen in your blood to help you learn when there may be an indication of important changes in your well-being. See your Sp O2 nightly average & range on wrist with an Sp O2 clock face & view trends over the past week in the Fitbit app Boost your energy with better rest Track your time in light deep & REM sleep then get a Sleep Score to better understand your ZZZs. & use the Smart Wake alarm to wake up during the optimal stage of sleep & be ready to take on your day. Dive in Sense is water resistant to 50 meters which means you’re free to track laps in the pool & wear it in the shower at the beach & beyond however please don’t take it into the sauna or soak in the bath with it on..