Google Maps app for iPhone, iPad and Android already shows you alternate routes when you request for it while navigating. Google has updated these apps to show notifications if there’s a faster route. Google maps already shows bands of red, yellow and green along your route based on traffic conditions. The new notification option now lets you reach the destination faster with dynamic rerouting so that you can avoid heavy traffic in your chosen route.
Google acquired Waze, popular crowd-sourced navigation app back in June and introduced real-time incident reports from Waze users for Google Maps for Android, iPhone and iPad in select countries. Getting traffic info would help dynamic rerouting since these updates are instant.
Both these apps have also been updated with bug fixes.