The science

How the hook works, and how we turned it around

ThenThat draws on published behavioural research and product design ideas. These explain the design; they do not establish that this app treats addiction or improves outcomes.

Variable rewards

Rewards that arrive on an unpredictable schedule keep a behaviour going more stubbornly than rewards that arrive every time. B. F. Skinner described these "variable-ratio" schedules in his work on reinforcement; they are the logic of slot machines, and of the refreshing feed.

In the feedPull to refresh. Maybe something great, maybe nothing. You pull again.

In ThenThatEvery check-in opens a drop. Usually a little XP; sometimes rare; once in a while, a jackpot.

Source: C. B. Ferster & B. F. Skinner, Schedules of Reinforcement (1957)

Triggers

Deciding in advance exactly when and where you will act — an "if-then" plan, or implementation intention — makes people markedly more likely to follow through than a general goal does. Peter Gollwitzer's research, and many studies since, found this across health, study and work goals.

In the feedA badge, a buzz, a red dot — or just boredom — and your thumb is already on the app.

In ThenThatYou write the trigger yourself: "When I get into bed, then I read a page." The cue that used to open the feed now opens the habit.

Source: P. M. Gollwitzer, "Implementation intentions", American Psychologist (1999)

Make it effortless

BJ Fogg's behaviour model says a behaviour happens when motivation, ability and a prompt meet at the same moment. When motivation is low, making the behaviour smaller is more reliable than trying to feel more motivated.

In the feedInfinite scroll and autoplay remove every reason to stop. Zero effort, zero friction.

In ThenThatEvery hook has a two-minute version. One page counts. Five push-ups count. The tiny version keeps the streak.

Source: BJ Fogg, Tiny Habits (2019)

Streaks and loss aversion

People feel a loss more strongly than an equal gain, a finding at the heart of Kahneman and Tversky's prospect theory. A streak turns "skip today" into a loss. ThenThat adds the shield because a habit is built by coming back, and an unforgiving streak teaches people to give up.

In the feedSnap streaks and daily rewards you would hate to lose — so you open the app to protect them.

In ThenThatStreaks, per hook and overall. But with a shield: one missed day in seven is forgiven, so one bad day does not make you quit.

Source: D. Kahneman & A. Tversky, "Prospect theory", Econometrica (1979)

Investment and progress

Nir Eyal's Hook Model ends each cycle with an "investment" that makes the next cycle more likely. Separately, the endowed-progress effect found that people who feel they have already made progress toward a goal are more likely to finish it.

In the feedFollowers, likes, a profile you have built for years. The more you put in, the harder it is to leave.

In ThenThatXP, levels and a feed of your own wins. What you build up here is proof that you did things.

Source: N. Eyal, Hooked (2014); J. C. Nunes & X. Drèze, Journal of Consumer Research (2006)

Riding the urge

"Urge surfing", developed by G. Alan Marlatt in work on relapse prevention, treats a craving as a wave that rises, peaks and passes if you watch it instead of acting on it. Noticing the urge is half the trick.

In the feedThe urge to check arrives, and the app is one tap away. It wins before you notice.

In ThenThatCatch the urge with the "about to scroll" button: swap it for one of your hooks, or ride it out with a 90-second countdown.

Source: G. A. Marlatt & J. R. Gordon, Relapse Prevention (1985)

How long does a habit take?

In a study by Phillippa Lally and colleagues, new daily habits took anywhere from 18 to 254 days to feel automatic — a median of about 66. Not 21. Missing a single day did not meaningfully set people back, which is why the streak has a shield.

Source: P. Lally et al., European Journal of Social Psychology (2010)

Read the research: Implementation intentions and Lally and colleagues on habit formation. The 90-second timer is a practice interval, not a prediction of how long your urge will last.

What we refuse to borrow

No feed of other people. The only feed is your own wins.
No push notifications. The one email is opt-in, in your evening, and only if something is left to do.
No streak you can lose for paying late. Everything that builds the habit is free.
No selling your attention. There are no ads, and there never will be.

ThenThat is a habit tool, not treatment. If your phone use is hurting you, a professional is a better first step than any app.

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