The research behind four habits, mends and chimes
Habits take longer than most people expect, one missed day does not undo them, specific plans and written-down progress help, and social support helped completion in one trial. Below are five published studies, with the numbers as the authors reported them and a plain statement of what The Habbits does because of each. These are external findings, not data from our users.
How long habits take and missed days
Habits took a median of 66 days to plateau, and one missed day did not materially change that. In a study of 96 volunteers who each picked one daily eating, drinking or exercise behaviour and tracked it for 12 weeks, the time to reach 95% of the plateau in automaticity ranged from 18 to 254 days; the median was 66 days for the 39 people whose data fit the model.
The authors also looked at 140 missed opportunities (after three days in a row of doing the behaviour) and concluded that missing one opportunity did not materially affect the habit formation process; performing the behaviour more consistently was associated with a better model fit. Of the 96 who started, 82 gave enough data to analyse.
Why The Habbits does this. A missed day is treated as normal, not as failure. In The Habbits a missed day mends: skip Thursday, do the habit on Friday, and the streak carries on, once per rolling week (see how mends work). The app does not promise a number of days to build a habit.
Limits. Participants reported their own behaviour and automaticity, and the behaviours were eating, drinking and exercise, not every kind of habit. The study did not test a rule like one mend per week; that limit is our design choice.
Source: Lally, P., Jaarsveld, C. H. M. v., Potts, H. W. W. et al. (2010). How are habits formed: Modelling habit formation in the real world. European Journal of Social Psychology, 40(6), 998–1009. doi:10.1002/ejsp.674
Planning when and where
Specific “if this, then that” plans had a medium-to-large effect on reaching goals (d = 0.65). A meta-analysis of 94 independent tests found that forming an implementation intention, a plan that says when, where and how you will act, had a positive effect of medium-to-large size on goal attainment (d = .65) compared with just intending to.
The plan can be as short as “After breakfast, I will take a walk.”
Why The Habbits does this. Habits can carry a cue, such as “After coffee”, and a reminder time, and the reminder then reads as that cue (“After coffee: meditate”). Setup is one sentence: “Every day I want to ___ and ___.”
Limits. The effect size is an average across many kinds of goals and settings; it is not a measure of this app, and individual results vary.
Source: Gollwitzer, P. M., Sheeran, P. (2006). Implementation intentions and goal achievement: A meta-analysis of effects and processes. Advances in Experimental Social Psychology, 38, 69–119. doi:10.1016/S0065-2601(06)38002-1
Tracking progress
Monitoring progress improved goal attainment (d = 0.40), more so when it was recorded or shared. A meta-analysis of 138 randomised studies (19,951 participants) found that interventions to prompt monitoring of goal progress increased goal attainment (d+ = 0.40, 95% CI 0.32 to 0.48).
The effect was larger when the progress was physically recorded and when it was reported to others or made public.
Why The Habbits does this. Each habit is recorded with one tap, and the week strip, the day’s count and the monthly mosaic make progress visible. Duet, the optional one-partner mode, lets one other person see that you did the same habit.
Limits. The reviewed interventions varied widely (diaries, apps, reports) and were not tests of The Habbits or of habit apps as such.
Source: Harkin, B., Webb, T. L., Chang, B. P. I. et al. (2016). Does monitoring goal progress promote goal attainment? A meta-analysis of the experimental evidence. Psychological Bulletin, 142(2), 198–229. doi:10.1037/bul0000025
Social support
A weight-loss trial found 95% completion with friends and support strategies, against 76% for people recruited alone. In a randomised trial of 166 people in a four-month weight-loss program, people recruited with three friends or family members and given social-support strategies had 95% treatment completion and 66% fully maintained their weight loss from month 4 to month 10; people recruited alone on the standard program had 76% completion and 24% maintained it in full.
Those recruited with friends also lost more weight at the end of treatment and at the 10-month follow-up.
Why The Habbits does this. Duet pairs you with exactly one person. When you both do the same habit on the same day, your chimes harmonise, with no feed and no ranking.
Limits. This was a weight-loss program, not a habit app, and the supported groups were four people with a package of support strategies. It does not show that a single partner, or Duet, produces these numbers.
Source: Wing, R. R., Jeffery, R. W. (1999). Benefits of recruiting participants with friends and increasing social support for weight loss and maintenance. Journal of Consulting and Clinical Psychology, 67(1), 132–138. doi:10.1037/0022-006X.67.1.132
Fewer goals
Planning for several goals at once can backfire. In a series of studies, benefits of implementation intentions for one goal did not typically carry over to multiple goals: planning drew attention to how hard it is to do many things, which undermined commitment to them.
The authors also found that framing several goals as manageable reduced the perceived difficulty.
Why The Habbits does this. The Habbits holds four habits and stops there, and setup asks for only two to begin with. A fifth means retiring one, and a retired habit keeps its history.
Limits. The study was about planning several goals at once, in everyday consumer tasks. It does not show that four is the right number; four is our design choice.
Source: Dalton, A. N., Spiller, S. A. (2012). Too much of a good thing: The benefits of implementation intentions depend on the number of goals. Journal of Consumer Research, 39(3), 600–614. doi:10.1086/664500
What we couldn’t find
We did not find a quantified, peer-reviewed result we trust for two other parts of the design: sound as a reward for a completed habit, and one-tap logging reducing friction. The chimes and the one-tap controls are design choices, not research-backed claims.
We also leave out a widely repeated “65% and 95% with an accountability partner” figure attributed to the American Society of Training and Development. We could not trace it to a primary study, so we do not use it.
Sources
- Lally, P., Jaarsveld, C. H. M. v., Potts, H. W. W. et al. (2010). How are habits formed: Modelling habit formation in the real world. European Journal of Social Psychology, 40(6), 998–1009. doi:10.1002/ejsp.674
- Gollwitzer, P. M., Sheeran, P. (2006). Implementation intentions and goal achievement: A meta-analysis of effects and processes. Advances in Experimental Social Psychology, 38, 69–119. doi:10.1016/S0065-2601(06)38002-1
- Harkin, B., Webb, T. L., Chang, B. P. I. et al. (2016). Does monitoring goal progress promote goal attainment? A meta-analysis of the experimental evidence. Psychological Bulletin, 142(2), 198–229. doi:10.1037/bul0000025
- Wing, R. R., Jeffery, R. W. (1999). Benefits of recruiting participants with friends and increasing social support for weight loss and maintenance. Journal of Consulting and Clinical Psychology, 67(1), 132–138. doi:10.1037/0022-006X.67.1.132
- Dalton, A. N., Spiller, S. A. (2012). Too much of a good thing: The benefits of implementation intentions depend on the number of goals. Journal of Consumer Research, 39(3), 600–614. doi:10.1086/664500
Numbers were checked against the published abstracts or full text on 6 October 2026. This page summarises research; it is general information, not medical advice.
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