I use Evernote for my journal, but I call it a diary.

I find I am using it as much or more than the do-list I keep in Trello....seems that I clarify my thoughts as I write and the process leads me to a better place than staring at a do list...

The idea of free journaling is very liberating. I am not the most consistent person. I generally write down thoughts or ideas that I feel impressed on me in the moment. I just drop everything I'm doing and write it down including the date, time and place I receive the mental download.

Like you I free-journal most often. I used to be really diligent about it, writing almost daily from the time I was a little kid in elementary school (using a hand-me-down little planner that my mom would get for free with purchase) until I was well into my twenties, but as life got busier I just fell out of the habit. Now I've been trying to get back to a more regular routine, but like you I don't want to force it. Instead I try to journal about once a week -- regularly enough for me to make it a "foundational habit" but not enough to make it too onerous. I've always loved keeping and sometimes going through my personal journals of years past, and having more than once experienced the horror of losing a digital journal entry (obsolete technology -- goodbye, floppy disks! -- or just random computer errors) I only ever do it now on pen and paper. I've tried various notebooks over the years but have settled on Moleskines and Leuchtturm notebooks for their quality and their ability to lie completely flat.

I don't use prompts...usually if I just start writing anything (even just "I don't know what I'm going to write") that's more than enough for me to get the thinking and writing juices going, and the next thing I know, I'm four pages into the entry. :-)