Some of our products have a unique Lifekey™ signature that is assigned to an individual when the product is registered. It's simple: Tap your Lifekey to let family and friends know when and where you start an activity — like running, biking, climbing or just chasing the dream... Once you start an activity, if something happens, your Lifekey functions as an important medical companion that can call for help, notify emergency contacts, or provide vital health data when it’s needed most. Tap to let family and friends know when and where you start an activity. Tap when you’re done to let your followers know you’re safe and sound.