Voice Alerts Only for Navigation

This next subtle but welcome CarPlay feature came as more of a surprise, since it’s not explicitly mentioned anywhere on Apple’s iOS 15 features pages — it just suddenly appeared up in the second iOS 15 beta.
While Apple Maps and Siri have always offered voice-guided turn-by-turn navigation, it’s generally been an all-or-nothing affair. You could mute the voice guidance entirely, and hear no alerts at all, or turn it on and listen to Siri chatter away to guide you through every turn and major interchange.
Fortunately, however, iOS 15 will provide a solution for users who would prefer something in between — you can now set Apple Maps to notify you of alerts and important navigation information only.
To facilitate this, the mute button has now been moved out of the menu and into an on-screen icon that now expands to show three options: on, off, or alerts only.
In alerts only mode, Siri will provide initial voice guidance when you first start your route, as well as letting you know when you’ve arrived at your destination. While traveling, however, Siri will only pipe up when it has something important to tell you, such as an accident, road closure, or detour, faster alternative route, or upcoming traffic camera.
This will also include reassuring notifications like, “Two lanes closed on Highway 401 eastbound in two kilometres. You are still on the fastest route.”
This actually isn’t a CarPlay feature, per se — it’s available in Apple Maps on the iPhone as well — but it’s definitely going to be the most useful when you’re in the car.