No, Karoo is an entirely standalone device that gives you all the tools in one place. You can adjust all your settings, profiles, and ride plans on your Karoo. Use your home WiFi to sync your routes, activities, training programs, and group ride information. With intelligent map layer syncing you can even build routes or make ride changes while offline and on the road.
You will be able to receive notifications on your Karoo 2 from your iPhone or Android Smartphone when you are in-ride. This is just a display notification and you cannot respond to texts or attend calls on Karoo 2.