A free program for Android, by EasyToolsApps.
The Screen Mirroring Assistant app is a powerful tool for mirroring your smartphone screen to a TV screen.
The first thing you need to do is to connect your phone and smart TV to the same WiFi network. On the other hand, if you are using a non-smart TV, you must use a wireless display adapter like Chromecast and connect the dongle to the WiFi network.
The next thing is to launch the app and click on the "Connect" button.
Now, you will be able to mirror your screen.
This tool is very easy to use and very powerful.
