Personally, I prefer to use a dedicated notebook. I find that it's faster and easier to type something like this out, but - like the learning process - I think there's something to engaging your brain in the handwriting process that makes it more effective.

I've tried both notebooks and apps, and both have their perks. Personally I like apps better, since typing is faster for me as well and I have my phone with me all the time, so it's easy to continue writing later, in the bus or something, if I don't have time to finish when I wake up. It just makes it easier for me to keep up the habit. Also sometimes I remember some extra details when writing and on phone it's easy to go back and edit things. One thing I like about paper is that I can draw things, sometimes that's easier than putting it into words.