Since Snapchat became popular for their expiring messages, videos and pictures, other messaging apps have been seeking to do the same thing. Facebook has added the ability in Facebook Messenger recently, and it looks like Google is going to do the same thing with Allo, which should be launching here in the next few weeks.
With incognito mode, your messages are secured with end-to-end encryption. But you also have the ability to set these messages to expire after a certain time, as well as private notifications. So on the lock screen, the notifications won't show the content until you unlock your device and go into the app. Keeping the message safe and secure. When it comes to the expiring messages, though, you can set to have these expire after 1 minute, 1 hour, 1 day or even 1 week. Giving you granular control over when these expire. Any of the participants in the chat can change how soon these messages will expire, and they will then become the default settings for all future messages in the chat.
Incognito mode in Allo appears to look pretty similar to what you see in Chrome with Incognito mode. The chat turns to a material design blue color, with the "Incognito Mode" background in the chat as well. To remind you that you are in an incognito chat. Allo appears to be going in the right direction in terms of encryption and secure chats. But at this point, it may become a bit confusing for users. Having all of these different features, from the beginning, is always appreciated, let's just hope that Google has some sort of tutorial in Allo when you first fire up the app, to explain what some of these features actually are. Otherwise, users are going to get pretty confused, pretty quickly.
Of course, Incognito mode allows you to share all of the same content that you would normally share in Allo chats. Things like text, voice messages, pictures, videos and much more. But if there is a time limit on when these messages are to expire, then they will be gone forever, after that time limit.