How do you grab that password that you have entered in your phone so you can use your laptop on a WiFi network that you have previously joined? It’s not as hard as you might think but does need a little know how. If you have rooted your android phone then it makes life easier, I am running Cyanogen Mod but you should be able to use similar methods to get the information.
Open File Manager, if you’re not using Cyanogen Mod then Root Explorer or OI File Manager is often recommended, you should find yourself in the Internal Storage area of the file structure and might have a numeric zero visible at the top. At this point many other tutorials might baffle you but because you’re only logged in as a user you won’t be able to see the folder /data/misc/wifi/.
Enter the app settings using the menu button and select General Settings, scroll down to Advanced and Access Mode, then select Prompt User Mode. Press the file manager button at the top to give you the folder structure menu and choose Home, you will now see the /data/ folder appear and when selected you’ll be asked to authorise elevated privileges, click Yes and you’ll be whisked away to the android superuser request screen, select Remember choice for 10 minutes to save you from having to deactivate it later and select Allow. Now you are essentially an admin on the phone and can roam about unrestricted, bear this in mind and ensure you don’t play with the unknown, click /misc/ and then /wifi/ so as to see the wpa_supplicant.conf file, open this file with Editor or a text app to view its contents and see passwords and ssid’s.
There are many places to find this information, one of my references can be found here for further reading: http://zackeryfretty.com/posts/retrieve-saved-wireless-passwords-on-android