You want to have lengthy, complicated and unique passwords for every website that you use but that rarely happens in practice because complex passwords are impossible for anyone to remember.
Some people rely on password managers like LastPass or KeePass - they store all your passwords in an encrypted database which is then protected by a master password. You enter the master password and you instantly have access to all your stored user logins and passwords. LastPass and 1Password also offers apps for mobile devices.
Here’s a simple open-source app that I am internally using for managing the passwords of my various online accounts. The app is called Secure Passwords and it generates unique and strong passwords using the secure bcrypt algorithm.
Secure Passwords is available as a web app that you can use from any browser on any device, as a Chrome extension, as an Android App that you can sideload or you can download the single-page app and save it to your Dropbox for offline use.
To get started, enter your user name (or login id), the site’s domain name where you are trying to log in (e.g. google or facebook), your master password and hit the generate button.
The generated passwords meet all the criteria for strong passwords - they are made of digits, special characters and letters are in mixed-case. The passwords are generated using bcrypt which is still resistant to brute-force attacks and therefore it will be impossible for anyone to decrypt the master pass phrase should any of password ever gets leaked online.
You only have to remember the master key (pass phrase) and tool will generate unique passwords base on the site name and the user name. Also, the tool computes passwords in your web browser itself and not a single byte of data ever leaves your machine.
Related reading: Keep your Online Accounts Safe and Secure