On my phone, you hold the home and lock button down to take a screenshot and if you take your finger off the home button and leave it on the lock button until the snap is gone. Or you can just download the app snap save and nobody will ever know.
there are many ways you can take a screenshot of another person's Snapchat without them knowing! Obviously it depends on the phone you are using but I'd say it is fairly easy.
Here you can find some apps that can help you with that. Apparently the best one is Snapkeep available on the App Store. It's free and there are no ads. To use it, you need to log in with you Snapchat details and then save all the pictures and videos you want.
Alternatively, you can have a look at this video that explains how to do the same thing without an app.
Basically if you don't want the app, do keep in mind that you need to press the screen, button and power button at the same time.
If you have an Android there are apps as well but I couldn't find a similar method that could work.
Hope this is helpful!
Some screenshot apps will allow you to take screenshot on SnapChat secretly. For iOS, there are SnapSave, Snapkeep. For Android, there is SaveMySnap. But it is not available on Google Play, so you have to go to its page and download the APK.
If you want to take screenshot on snapchat without being detected then check this source .
Some very valid points!
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