We use WOW!Desk for all our ticketing & communication from clients we are currently working w/ - they've been great so far!! They have helped us keep track (and be more organized) about what's going where when communicating back& forth via email or phone calls etc...
I wish there were some other options available as well though since sometimes you just need something simple like "Send me this document" but don't want anything complex at times too haha :) Customer Service team members who work within wow desk can also create custom fields which makes organizing even easier than before now :).