It allows you to take screenshot of anything on the screen.

You can either press the “Power” and the “Volume down/Home” buttons at the same time for 2 seconds or tapping on its overlay icon which is for Android 5.0 and higher.

Once the screenshot is created, you can edit it immediately in this tool’s image editor.

Is there a way to screenshot Snapchat without them knowing?

Doing this will still notify Snapchat users that you’ve recorded content. That means you’ll have to do as you would when taking a normal screenshot: load Snapchat without clicking on the snap you want to open. Turn on Airplane Mode then use the screen recorder. Open the snap.

How do you secretly save Snapchats?

Those files can then be saved to your Camera Roll with the tap of one button. You must save the snap in Snapkeep before viewing it through the official Snapchat app, or it is permanently deleted.