Sprites
How habit strength works
Most habit trackers count your streak: how many days in a row you’ve done something. Miss one day and it’s back to zero, even if you’ve kept the habit for months. Sprites doesn’t count streaks. It tracks how strong each habit is, which is closer to how habits really work.
What you see
Each habit is an orb in your sky. As the habit gets stronger, the orb rises and glows brighter. Each habit also has a word for how far along it is:
- Just starting
- Taking shape
- Getting established
- Well established
- Second nature
Streaks and Sprites side by side
| Streak | Sprites | |
|---|---|---|
| You miss one day | Back to zero | Nothing changes |
| A year-old daily habit, then a five-day break | Back to zero | Slips from Second nature to Well established |
| You miss two days of a habit you’ve kept for four months | Starts again from one | Back where it was the day you pick it up again |
| A habit you do three times a week | Counts days in a row | Do it three times a week and it grows as well as a daily habit |
How a habit gets stronger
The first few weeks make the biggest difference. After that it keeps growing, just more slowly. That matches what researchers found when they followed people forming new habits (Lally and colleagues, 2009).
If you do a habit every day, it’s Taking shape within a week, Getting established at three weeks, Well established at about seven weeks, and Second nature at about thirteen.
Not every habit is daily. If you plan three times a week and do it three times a week, that habit grows just as well as one you do daily. It doesn’t matter which days you pick: Monday, Wednesday and Friday count the same as three days in a row.
Missing a day
The same study found that missing one day made no real difference to forming a habit. So in Sprites:
- Missing one day never weakens a habit, however new or old it is.
- A daily habit only starts to weaken when you miss two days in a row. Missing two days in a week with a day done in between is fine.
- For a habit you do a few times a week, being one short in a week is fine. Two or more short, and it weakens a little.
- A once-a-week habit can go nearly two weeks without weakening.
Old habits are harder to lose
The longer you’ve kept a habit, the less a few missed days hurt it. In the study, a habit took a median of 66 days to become automatic, so after about ten weeks Sprites treats a habit as established.
Take a five-day break as an example. A three-week-old daily habit drops from Getting established right back to Just starting. A habit you’ve done every day for a year only slips from Second nature to Well established.
Getting back on track
Picking a habit back up is easier than starting it from scratch, as long as the break was short (Wood and Rünger, 2016). So when a well-established habit slips, the first day you do it again makes up for the break. Miss two days of a habit you’ve kept for four months, and you’re back where you were the day you pick it up again.
This only works for habits that were already strong:
- A new habit doesn’t get much back. It hasn’t had time to become established.
- After a break, a habit needs a few clean weeks before it gets this benefit again. A habit that keeps slipping doesn’t get it.
- The longer the break, the less comes back. Take a habit you’d done daily for three months. After two weeks away, your first day back puts it straight back to Well established. After four weeks it comes back as Getting established. After eight weeks it’s back to Just starting.
Letting a habit go
A habit you stop doing fades over a couple of months. If you no longer need it, you can retire it, and it stays in your sky as a faint, distant star.
It all happens on your phone
Sprites only records which days you did each habit, and works out the strength from that. If you fix a day from last week, it comes out exactly as if you’d ticked it on time. None of it leaves your phone.
References
- Lally, P., van Jaarsveld, C. H. M., Potts, H. W. W., & Wardle, J. (2009). How are habits formed: Modelling habit formation in the real world. European Journal of Social Psychology, 40(6), 998–1009.
- Wood, W., & Rünger, D. (2016). Psychology of habit. Annual Review of Psychology, 67, 289–314.