Timely topic for me. I had the intention to keep a journal before I first entered therapy and did it a few times, but then started sending emails to the T instead (that is an old issue of mine). My former therapist suggested journaling instead of emails to him but he also got engaged in the emails a lot and everything became quite messy so the journaling nevever got realized. Now my current T says it's okay for me to email whenever and said that he would read everything, but it's clear that he does not (I totally understand). So just decided that I will now really switch to journaling instead as the emails just make me feel crazy and ashamed and it's not really an interaction anyway.

I don't like handwriting much and prefer digital technology for pretty much anything possible, so I signed up to Penzu (also mentioned by annielovesbacon above) because they also offer a free mobile app.

What I plan to put in the journal. I have a habit of sending an email to T after each session and typically a few between sessions (although less than I used to) about additional thoughts and feelings in response to what was discussed in the session or whatever else that comes up. I actually like the idea of the journal now because I can certainly put stuff in it that I would not tell the therapist. We'll see how it goes. Have not told T yet.