Not sure if this qualifies, but for the past 3 years I’ve been using a spreadsheet with a tab for each horse. I started it to plan and track conditioning for my eventer. My husband jokes that spreadsheeting is one of my favorite hobbies, so it was a natural choice. I wouldn’t have the patience for long journaling.
I plan and track date, type of ride, and location if not home. I have a column for notes that I leave blank if there’s nothing remarkable about the ride, and additional columns as needed (Equiband time used, video taken, whether there was headshaking and if so what the weather was).
I like it because I can use Google Sheets on my phone to update very quickly, often even while I’m cooling the horse down. Having notes on the date I did something or exercise progression during rehab has come in handy several times. Also it’s free and it’s searchable.
If I don’t ride for some reason other than horse’s day off I’ll note weather, work, farrier day, etc.
I also have a column in the eventer’s tab for my own workouts (just type and duration).