I use an app I made called ghostnote which basically allow you add attach notes in context of what you are doing currently working on. But I like your idea of u

I use an app I made called ghostnote which basically allow you add attach notes in context of what you are doing currently working on. But I like your idea of using messenger or something like that as a, even more, laissez-faire approach The whole point is to write the idea down, not so much remembering it (unless you literally have the melody for a hit song or the algorithm for the cure for cancer)