CSV with some cloud sync solution. I turned the overhead of manually logging an activity into a feature of committing to a task. I log Date, Start Time, End time, 'Project', and location. When I feel myself losing focus I end the task and take a break. Early inspiration from Cal Newport.
Supplement this approach with a small paper notebook (originally I used 3x5inch pocket then moved to a 5x8 inch) where you no longer need your phone/computer to log entries (enter them later). I'm collecting a nice physical library of notebooks that are chronologically ordered and contain everything from in depth technical tasks to notes on groceries. Also acts as a good spot for stickers collected on your travels.
Regarding transactions, I've started using everydollar.com. I've only started using it in 2019 so I cannot 100% vouch for it yet.
Supplement this approach with a small paper notebook (originally I used 3x5inch pocket then moved to a 5x8 inch) where you no longer need your phone/computer to log entries (enter them later). I'm collecting a nice physical library of notebooks that are chronologically ordered and contain everything from in depth technical tasks to notes on groceries. Also acts as a good spot for stickers collected on your travels.
Regarding transactions, I've started using everydollar.com. I've only started using it in 2019 so I cannot 100% vouch for it yet.