You can ensure the privacy of your users' information in a few possible ways. 

First, you can use the private view APIs available for iOS, Android, and React Native. On all 3 platforms, this will cause a black box to appear over the specific views set as private.
​
Secondly, your users will have the option to blur out sensitive information in the captured screenshot as displayed in the image below. 

In addition, if you prefer to disable screenshot and video attachments entirely, you can control this from your side (see instructions for iOS and Android).
​