A free app for Android, by Emam.
Recover Deleted Messages is a handy utility for Android smartphones that allows you to restore deleted messages from your device's notification center, without having to root your device. The tool scans the messages, looking for deleted ones, and then it offers you the possibility to restore them, either in the form of text, audio, images, or even videos!
To use the app, simply select one of your favorite messaging apps (Facebook Messenger, WhatsApp, Instagram, and more) and start it. Then, choose the notifications that you want to check for deleted messages and click on the "Restore" button. That's all! The app will do the rest of the work for you. It will search for the deleted messages and then restore them for you, one by one.
The app is very easy to use and doesn't require you to do anything else but start the app.