WiFi Password Show is an app that displays all the passwords for all the WiFi networks you've ever connected to. You do need to have root privileges on your Android smartphone to use it, though. It's important to understand that this app is NOT for hacking WiFi networks or anything like that. It's simply to see the passwords you've already entered for networks you've already connected to.
The main function of WiFi Password Show is to help someone connect to your WiFi network without any hassle. To do just that, tap on one of the available networks to share the password in many different ways: with a QR code, via email, by copying it to your clipboard, or displaying it on a full screen with colorful letters that are super visible.
WiFi Password Show is an app that's much more useful than it may seem at first glance. Thanks to this app, you won't have to check the back of your router to remember your password whenever someone new comes over and asks to connect to your WiFi.