On Android and iOS, the Snapchat messaging app has an update. If the version for iOS stands out with the double tap on the screen during a recording to switch from selfie mode to that classic for shooting, a common point is at the authentication level.
Two-factor authentication indeed marks its arrival. It relies on entering a six-digit code sent by SMS when trying to connect to Snapchat with a new device. A way to verify that it is the legitimate user and not a usurpation.
This kind of two-step authentication is increasingly offered but it is not said that it is actually used. As with Snapchat, it is often optional.