In this post I present some of the issues that I experienced with this powerful ultrabook and how I solved them.
At the beginning I couldn't enable the bluetooth but after the first Ubuntu update it worked perfectly.
Additional Tip: if you want to send files from your phone to your computer you should do search and find "Personal File Sharing" in the dash and activate both the checkboxes under "Recieve Files over Bluetooth, as commented by Reza Ghayem in AskUbuntu.
By default there are some issues with the stability of WiFi connections. If your WiFi connection is not stable (ie: disconnects and reconnects a lot) you should run the following in a Terminal:
sudo apt-get install linux-generic-lts-quantal
and reboot your computer after that as suggested by Dan Wood in this AskUbuntu post.
Warning: Some people have reported some problems (ruins installation) using this hibernate tip when the Home directory is encrypted. I haven't confirmed this, though.
Although in my case Suspend worked from the beginning, Hibernate didn't so just installing uswusp solves the issue:
sudo apt-get install uswsusp
There are additional instructions suggested here but they weren't necessary. After installing uswsusp you can try hibernating your computing executing in a terminal:
If it works then you just have to restart the computer (after waking it up) and check hibernate through the standard options in Ubuntu (right top button-->Hibernate).
And that's it! Just let me know if you have additional hacks needed for Dell XPS 13 Developer Edition or if you had any problem with any of these solutions!