Diary is an indie developer diary built over the course of 12 years with many features and settings.
Diary comes as a portable app or an installer. It's not the most polished app, but it comes from an indie developer and is simple enough to use. Right away you'll notice dates, passwords, search, images, files, On this day, to-do lists, and more. Plenty more.
To get started, you'll need to enter a password and all features will then become available. After, all, it's a diary.
As you write, everything is saved so you can move from day to day, or whatever you like, without looking for the save button all the time.
Again, while Diary might not be as polished as a professional app, we were surprised at the numerous settings, options, and features.