If you were with someone when they stopped breathing and their heart stopped, would you know what to do? Could you save their life?
Even if you have been trained in CPR in the past, in the heat of the moment, would you be able to remember just how many breaths to do per minute, and how many times you need to pump the person's heart?
In order to help people perform possible life-saving CPR correctly, St John has released an innovative app for iPhone, Android and Windows Phones, available free from iTunes, Google Play or WindowsPhone.com.
The app has great features like beeping and vibrating "CPR Timing Assist" to help you perform consistent chest compressions. The instructions can be spoken aloud from your phone, keeping your hands and task on the vital job of CPR.
There are other options, including Adult, Child and Infant CPR tutorials.
This is one app everyone with a smartphone should install, especially given this startling statistic - every day more than nine New Zealanders suffer a cardiac arrest, but only 10% of them will survive.