If you need to reinstall Ubuntu or if you just want to install a new version from scratch, wouldn’t it be useful to have an easy way to reinstall all your apps and settings? You can easily accomplish this using a free tool called Aptik.
Aptik (Automated Package Backup and Restore), an application available in Ubuntu, Linux Mint, and other Debian- and Ubuntu-based Linux distributions, allows you to backup a list of installed PPAs (Personal Package Archives), which are software repositories