If you have the first version, you should be all set.
The developers talk a lot about end to end encryption. Im pretty sure we all use iCloud and most of us are not willing to pay vastly more amounts of money just for something most of us dont even want.
First version works fine (if you have it). Ill continue to use that until another competitor comes around.
Quality reviewer about
Day One Journal: Private Diary, v2.3.5