Storytime
Open most people's to-do app and you will find, somewhere near the bottom, an item that has been rewritten every week for a year. "Stretch." "Read." "Call mum." It gets ticked sometimes. It gets copied forward more often. It never goes away, because it is not the kind of thing that goes away.
Here is the distinction, and it is the whole article. A to-do list holds things you do once: they have an end, and the point of the tool is completion. A habit tracker holds things you do again: they have no end, and the point of the tool is consistency. Both are lists with ticks in them, which is exactly why people put the wrong things in the wrong one.
Why the distinction is not just semantics
Repeated behaviour is a genuinely different category, not just a task that happens a lot. Wood, Quinn and Kashy sampled what people were actually doing hour by hour and found that a little over 40% of everyday behaviours were repeated in the same place almost every day, with little in the way of conscious choice (Journal of Personality and Social Psychology, 2002). Wood and Neal later described what that means mechanically: a habit is a response cued by a context, not a decision reached on the merits each time (Psychological Review, 2007).
A task and a habit therefore want opposite things from a tool. A task wants to be remembered until it is done and then to disappear. A habit wants a stable context, a repetition count and a visible history, and it specifically does not want to disappear, because disappearing is what it is trying not to do.
There is no research comparing habit-tracking apps with to-do apps. Nobody has run that study, and anybody who quotes you a figure for it has made it up. What follows is the mechanics, applied.
What goes wrong when a habit lives in a to-do app
It is rewritten every day, and the rewriting becomes the habit. Recurring tasks help, but you still start each day at zero, with no visible sense of a run. The item is a fresh obligation each morning rather than the continuation of something.
The history vanishes. A completed task is designed to be got rid of. That is the right behaviour for a task and exactly the wrong behaviour for a habit, where the only thing you actually want to look at in three months is the pattern: which days, which weeks, what happened after the holiday.
It competes with real deadlines and loses. A habit sitting in a list beside "reply to the landlord" and "file the return" will lose every single time, because the other items have consequences and it does not. Not today, anyway. Habits are a slow claim against a fast list.
Ticking it means nothing, and you can feel that. In a to-do app, a tick means an obligation has been discharged. For a habit on day three of a year, discharging the obligation is not the point, and the tick does not carry the one piece of information you want, which is whether this is becoming normal.
What goes wrong when a task lives in a habit tracker
The mirror problem is less common and more annoying.
A one-off sits at zero for ever. Put "sort out the loft" in a habit tracker and it becomes a daily failure, which is an impressive way to make a small job feel like a character defect.
It drags the record down. If your tracker shows a consistency figure of any kind, a one-off with one completion and 90 non-completions is noise in the only number you were meant to be reading.
It never ends, so you never get the satisfaction. Finishing a task is genuinely pleasant. A habit tracker has no concept of finished, and deliberately so, so it cannot give you that.
The test: will this be on the list again next week?
One question sorts almost everything.
If the answer is no, it is a task. "Book the dentist" is a task even though you will book a dentist again in six months, because the next one is a different item with a different date. Put it on the list, do it, let it disappear.
If the answer is yes, in the same shape, it is a habit. "Ten minutes of Spanish" will be there next week in exactly the same form. It goes in the tracker.
There is a third answer, and it is the interesting one: "yes, but I do not know when." Exercise, admin, tidying and practice all tend to live here, and "whenever I have time" is the reliable killer of habits, for the reasons in why where you do it matters. The fix is to make the answer specific before the item goes anywhere. Once it has a day and an anchor, it is a habit. Until it does, it is a wish with a tick box, and neither tool can help.
If you want a record that treats a missed day as a missed day, Seeded does that, and it is free for three habits on iPhone. A cap of three is a reasonable shape for this test: if more than three things pass "will it be there again next week", most of them are tasks wearing a costume.
When you genuinely need only one
Plenty of people do, and it is worth saying which.
Only a to-do list if your life is mostly projects with ends: deadlines, deliverables, admin, other people's dates. If you have no repeating behaviour you are actively trying to establish, a habit tracker is a solution without a problem, and you should stop reading.
Only a habit tracker if your obligations are simple enough to hold in your head and the thing you are actually trying to change is repeated behaviour. A lot of people in this position keep a to-do app out of habit and use it for three items a week, which is three items too few to justify the app.
Most people need both, and the useful realisation is that they do not need them at the same size. The to-do list can be long, because tasks arrive from outside. The habit tracker should be short, because habits are chosen, and the number you can form at once is small. There is a good argument for making it exactly one, in one thing at a time.
Using both without doubling the admin
Three rules keep this from becoming a hobby.
Keep the tracker tiny. Three or four items, all small enough to survive a bad day. If maintaining the tracker takes longer than doing the habits, you have built a second job.
Let items move. A habit that has become genuinely automatic can leave the tracker altogether: you are not tracking teeth-brushing. A task that keeps coming back in the same form has been telling you for months it is a habit. Move it.
Never mirror. Do not put the habits in the to-do app as well "so they are in one place". Two records of the same thing means neither is trusted, and you end up checking both.
The underlying difference is not really about apps. A task list is a memory aid for things you might otherwise forget. A habit record is a cue and a history for things you are trying to stop having to remember at all, which is what the habit loop is doing while you are not watching. If you are choosing a tracker, it is worth knowing what you want it to show you: why streaks backfire, and what to track instead makes the case that the most common answer is the wrong one.
Seeded is a habit tracker for iPhone that does not shout. A habit can be a plain check, a count or a duration, which is the range a repeating thing needs and a one-off never does. Three habits, the journal and time capsules are free. Get it on the App Store.
Bitesized
- A to-do list is built for completion. A habit record is built for consistency. Same interface, opposite jobs.
- A little over 40% of everyday behaviour is repeated in the same context with little conscious choice (Wood, Quinn and Kashy, 2002), which is why repetition is its own category rather than a task that recurs.
- In a to-do app a habit is rewritten daily, loses its history and competes with deadlines it cannot win against.
- In a habit tracker a one-off sits at zero for ever and drags the record down.
- The test for any item: will this be on the list again next week, in the same shape? Yes is a habit, no is a task, "yes but I do not know when" is neither until you give it a day.
- Most people need both. The list can be long. The tracker should be short.