Badly conceived "to do" lists don't work, and it is not just because of context, or what tool one is using. It is really about whether or not you list small-enough actionable items that have a concrete condition of "done-ness".

Each item in a to-do list that is carefully thought out will contain a verb, an object, and an implicit/explicit way to know that the item is complete. More importantly, each item describes a discrete action and not a huge project that may require a large indeterminate number of actions. A to-do list should contain a list of items that can be completed in a matter of hours or at most a day or two.

For example, "secure the business" has no objective way to know that it is actually complete; that is a huge project consisting of perhaps hundreds or thousands of specific actions. It does not belong on a "to do list".

There will never be an "app" that solves the problem of to-do lists. The problem of to-do lists is that people put the wrong things on these lists.