You can try the following cli to keep your droplet up-to-date, clean and secure:

apt-get update && aptitude dist-upgrade -y && apt-get autoremove -y

HTH

You may want to also run sudo apt-get dist-upgrade

You may also be interested in `aptitude`, which is a command-line, "graphical" interface to the package manager. It can be installed with the following command:

sudo apt-get install aptitude

After running `sudo aptitude`, the following basic commands are used for navigation:

* `Ctrl-T`: open the menu bar.
* `+`: mark a package for installation.
* `-`: cancel the pending installation of a package.
* `g`: Proceed to the package selection confirmation screen.
* `g`: Press again to confirm your selection.
* `q`: Or press to close the current view and return to the package list.

These are the absolute basic operations, of course. For details, see the documentation:

http://algebraicthunk.net/~dburrows/projects/aptitude/doc/en/

Chapter 1 is a good starting point, and `aptitude` can really be a great tool to get to know!

Run these two commands:
sudo apt-get update

and then

sudo apt-get upgrade
say "y" when they ask you for confirmation