Thanks! To be honest, the thought of using the relative path didn't even cross my mind. I just went for the "So... how do I make sure Kindle is connected before I do anything else..."
Maybe I just skipped the obvious solution because I'm pretty much the only one in my family/circle of friends who knows his way around technology so I'm inclined to do anything as easy and self-explanatory as possible. At the end of the day, I like having control as much as the next geek but 9 out of 10 times just double-clicking something to get results beats a whole bunch of buttons.
Also, at first I wanted to make the app with GUI and a choice of different formats. But it's midterms and there is always time for doing upgrades.