A half swipe on Snapchat is one way to read a message without sending a delivery notice, but the new version of the app seems to have deleted the feature. What is this? When you do half swipe, the sender doesn't get any notification that the chat was opened.

Is the half opened snap notification real?

Half Snap Notification: Will Snapchat Tell You If A Snap Is Half-Opened? ... This is not a real Snapchat feature, so don't worry. Your friends won't be notified about your half-opened Snap shenanigans.

What happens if you half open a snap?

Users on Snapchat know that you swipe left to open a message, but they also discovered quite quickly that if you half-swipe, you can see the message without sending the other user a notification that it's been seen. It's an effective way of previewing a message before deciding whether you want to respond.