Snapchat is one application to post temporary messages. Messages are temporarily available after they have an expiration date. But it seems that Snapchat programmers added an extra feature to the conversations.
The new feature allows you to delete a message that has been sent on Snapchat. It works in one-on-one messages, but also in group chats. 
Let's see how you can delete a message sent to Snapcaht.
First you should first update your Snapchat app to the latest available version. The function works only in the updated version. This means that if your friends are using an older version of the app, you may not be able to delete a message that you have sent in a face-to-face conversation.
After updating the app, you can test the feature by sending a message to a contact you know has the latest version of the app. Long press the message you just sent and a menu will appear. You will see that there is one choice "Διαγραφή."
For the new feature to work, several conditions must be met. In the initial tests, you may not see the Delete button, or when you first delete a message, the application will tell you that it will try to remove it from your friends' side. However, he may not. The reason; A bad internet connection, or an older version of Snapchat from your friends' side.
Όταν διαγράψετε ένα μήνυμα στο Snapcchat, θα σας εμφανιστεί στην οθόνη σας το 'Διαγράψατε μια συνομιλία." Ωστόσο ο φίλος σας δεν θα δει το ίδιο μήνυμα.
The best way to make sure your message has been deleted is to do so as soon as possible after sending it. If your friend has not seen the message, you should delete it before it appears in the conversation.
With Snapcchat group conversations, you can delete your message even if it has been seen by half.
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