Phil has written about Things. I'm also a long-time Things user but have often been tempted by other ToDoErs. I like, for instance, the way that Apple Reminders will let you set a Reminder when you get to a particular location.
But I've decided to stick with Things because I think I'm going to need it to see me into the forgetfulness of old age. It's already almost reflexive for me. If I think of a Thing I need to do I stick into Things. I'm not quite at the stage of putting something in Things at the top of the stairs for when I get to the bottom, but I'm not far off. And I think that's a good habit to cultivate. My fingers know where to move, I don't have to think about it. I want adding a Thing to be as natural to me as opening a door, so I don't forget my way to remember.