All in all, they're Google's attempt at helping you keep your data private a little easier.
Google Maps
Google Maps for one is getting an incognito mode that works similar to what the Chrome browser has. Google Maps is always tracking your movement across regions, and this basically lets you stop that. Maybe you don't want certain kinds of recommendations cluttering up your notifications. Maybe you want to hide your activity from your spouse (in which case you have other problems mate) or maybe you just think it's creepy Google tracks you all the time. Either way, incognito mode can stop Google seeing what you search for or where you travel.
Simply go to the app, tap on your profile photo, and click the appropriate button to activate the mode. It'll become available on Android later this month, with iOS to follow soon.
YouTube
YouTube is getting a new auto-delete function. What that means is, you can set a timer so that your history of videos watched is only available for a limited time, like three months. Everything before that is deleted, and as time passes your history is cleared as well. Of course, you can still delete videos manually if you prefer.
Google Assistant
One minor new interaction launched to the Assistant lets you ask it how your privacy is protected. Just ask, "Hey Google, how do you keep my data safe?" for more information. It's probably not something many people will use though.
Additionally though, another new feature being launched soon will let you delete your Assistant activity with voice commands. Just say, "Hey Google, delete the last thing I said to you," for instance, and your Assistant activity will go poof. You can also do this for longer time periods like asking it to delete everything you did with the Assistant last week.
It may not sound like a lot, but it's a big deal considering the recent hubbub surrounding human employees transcribing Assistant recordings so it could be trained more. This way, you can be sure the Assistant doesn't store any recordings you don't want it to. This feature will roll out over the next few weeks for English first, and other languages next month.