Sometimes, low-tech is the way to go. Writing things down can help reinforce memory, which is why so many instructors insist students take notes by hand.
I try to have pads and pens EVERYWHERE! I think every room of the house has at least on writing instrument and paper. Ironically, much of the time, I’m going crazy trying to find a pen or pencil, and I’ve even had to resort to using a crayon when a bout of creativity hit me.
Writers benefit a great deal by getting their ideas out of their heads for later reference. A slip of paper hanging on the wall can be more readily available than info buried in an app. Many of us also have a tendency to ignore notification dings and buzzes, so jotting things down is the best way to go.
Check out how I manage some of my story ideas.