> Playing devil's advocate here but can you effectively be wandering the grocery store looking for item X at the same time as your wife is looking for item Y wh

> Playing devil's advocate here but can you effectively be wandering the grocery store looking for item X at the same time as your wife is looking for item Y while she remembers that you should get Z instead of X and update the list in a manner which you'd be notified? I can't imagine that's common enough to warrant a real time todo list app but the scenario I'm familiar with is different from yours so I might be wrong. You have to ask, is SMS good enough? SMS is definitely good enough, but it's a nice-to-have to keep everything on the same list. That way when we meet up again we can scan the list and know everything's there. As for your scenario, yes, and it has happened. I'll be wandering the store, refresh the list and notice new things on the list. We currently use Cozi and while it isn't the best application ever it definitely gets the job done, and it's free.