Snapchat for iOS update adds CallKit support, enables Cat Lenses
Moreover, the latest update makes it easier to call Snapchat users without having to go through your Phone application. Thanks to CallKit support, all calls will appear in the Recents list and you'll be able to call anyone appearing on that list.
Also, you'll now be able to answer voice calls from friends without having to open Snapchat, as they will now appear in the incoming calls interface. Last but not least, notifications via CarPlay will be available as well.
Snapchat is not the first app to add CallKit support and surely won't be the last. Facebook Messenger, Google Hangouts, and Skype are just some of the apps that feature CallKit support for quite some time now.