Notes on paper or notes on your iPad, we do both or either. I sometimes even type notes directly into my computer if they are notes from a phone conversation while at my desk. All notes get printed out and put in the file, always a hard copy. Some apps can take notes and let you take photos to insert into the notes. Some apps automatically date and time stamp also.
Most important thing about notes is DOING THEM and they should be timely, not done the next day or a week later when you remember to.
Just my three cents worth (because I talk too much 🙂