In an emergency you may be unable to tell first responders critical information about your health. But if you take a few minutes to setup the Medical ID in your iPhone, it may be able to provide the health information they need. Apple.com already has a thorough web page about it so there is no need to repeat the steps here. This Apple Support page will give you the steps to set up your Medical ID and make it available from the lock screen for emergency personnel. Android manufacturers provide something similar as well. A friend of mine who is a medical professional told me about this feature and how much emergency professionals rely on it to help those in critical situations so share this tip with the people you love.