Automatic Emergency Braking or AEB uses a variety of sensors to determine if a forward collision crash is imminent and automatically applies the brakes to diminish the severity or avoid a crash entirely.
The auto industry agreed to make AEB standard in cars by 2022, but many vehicles have it available today. The systems are extremely good, though you absolutely shouldn’t rely on it to stop you — it’s meant as a last resort for when the driver isn’t paying attention, and it’s extremely alarming when the system does engage. While Apple CarPlay and smartphone apps are important, this one could save your life, so it’s worth making this one a high priority on your shopping list.