Stickies are great for quickly jotting down a short sentence or to-do item. I like having a few sticky notes on my iPhone Home Screen as it makes them always visible and forces my attention. I don't have to go inside any app to see them, which surprisingly often results in finishing the job mentioned in those sticky notes on time.
If you feel the same or want to try it out, here's how to add, edit, and use sticky notes on your iPhone or iPad Home Screen and Lock Screen.