A free program for Android, by Development Colors.
This app allows you to get notified when you receive a message or a file in your WhatsApp, Telegram, Instagram, or other chat apps. It will notify you with a sound and a notification. This application is free and easy to use, and you can select which applications and folders you want to monitor.
It has a very simple user interface, so it’s easy to use, and the installation is very fast. You don’t need to connect to the Internet to get this application to work, so it’s compatible with your data plan.
The application is capable of monitoring changes in notifications and files for all apps that you have on your device, not just WhatsApp, Telegram, and other chat apps. You can also save a history of the notifications you choose.