I only have a traffic-limited mobile broadband connection at my disposal. sudo apt-get dist-upgrade wants to get ~500MB of data which is not feasible for me right now.

Hence, is it possible to only upgrade certain applications, e.g. Firefox?

I am quite aware that some libs must be upgraded as well, but 100MB a day won't hurt, 500MB do.

Basically, I want to split up the upgrade-process into little chunks over the month so I don't exceed my daily quota just by downloading updates.