Otto's Free App Blocker

How to use your phone less

This is long and it's referenced, because most writing on this subject is confident about things the research doesn't support. Everything below either cites a study or says plainly that it doesn't have one. On notifications the evidence flatly contradicts the standard advice, and I've gone with the evidence.

Written September 2026. I make a free app blocker, so I'm not a neutral source and you should read this knowing that. What follows is what the trials found, including the parts that are awkward for anyone selling a blocking app.

1. Four things to get straight first

"Phone addiction" isn't a diagnosis

Neither the DSM-5-TR nor the ICD-11 recognises smartphone addiction or social media addiction. ICD-11 lists gambling disorder and gaming disorder. The American Psychiatric Association's proposed internet gaming disorder sits in a section for conditions needing further study, and the APA says outright that it doesn't cover general internet, social media or smartphone use. Researchers call it problematic smartphone use. One review that tested the behaviour against the standard addiction criteria concluded the label wasn't justified.

That distinction does some work. Deciding you're an addict is the kind of internal, permanent, "this is just who I am" explanation that predicts giving up after the first slip. It's also the framing used to sell things. Plainer language is better: you're on your phone more than you want to be.

Your estimate of your own use is wrong

Researchers compared self-reported phone use against logged use across 106 effect sizes. Self-report was only moderately correlated with reality and systematically off. In a study of 238 iPhone users, a plain "how many hours?" guess beat most of the validated addiction questionnaires, and only 56.5% of the people the phone data flagged as heavy users put themselves in that group. Another study had people estimating 37 daily checks against 85 real ones.

So read the number off the device rather than out of your head. And treat any "are you addicted?" quiz as a measure of how worried you are, not how much you use it.

Less screen time doesn't automatically mean a better life

Most guides skip this one. A preregistered field experiment put greyscale against goal-setting. Greyscale cut objectively measured screen time straight away, and had no causal effect on wellbeing or academic performance. A systematic review of 21 digital detox studies covering 3,625 people found use went down every time, while the wellbeing results contradicted each other and several studies found negative affect and loneliness going up.

The trials that did produce real wellbeing gains explain why in their own mediation analysis. The benefit ran through what people did instead: seeing people, exercising, reading, sleeping. Removing the phone reliably removes the phone. Everything after that depends on what fills the hole.

Almost everyone rebounds

One trial capped students at two hours a day for three weeks. Depressive symptoms fell 27% and sleep quality improved 18%, and screen time climbed again as soon as the three weeks were up. In a two-week mobile internet block, daily screen time went from 314 minutes to 161, then back to 265 once the block lifted.

So treat all of this as a permanent change to how your phone is set up, not a challenge you finish. A thirty-day detox that ends is a thirty-day detox that ends.

2. Why the phone wins

It's a habit, not a decision

Somewhere between 35% and 43% of daily behaviour is habitual, meaning performed almost every day and usually in the same place. That comes from experience-sampling work by Wendy Wood and colleagues, on student samples, so treat it as a range rather than a fact. Phone checking fits the description: short, frequent, triggered by where you are rather than what you intended, and mostly invisible to the person doing it.

The clearest demonstration of what that means is the stale popcorn study. Habitual cinema popcorn-eaters ate as much week-old popcorn as fresh popcorn, but only in a cinema. In a meeting room the same people ate according to whether they liked it. Making them use their non-dominant hand broke the habit and preference came back. Habits are tied to context and to physical routine, which is the reason moving an icon works better than resolving to be different.

The reward is unpredictable, and that's deliberate

Feeds run on the reinforcement schedule that makes slot machines work. The reward is real but you can't predict which pull delivers it, and that sustains the behaviour far better than a reliable reward would. Natasha Dow Schüll's ethnography of machine gambling design documents the engineering behind it, and designers who worked at the large platforms have said publicly that the mechanics were borrowed knowingly.

What you're avoiding is often the real subject

Boredom proneness is robustly associated with problematic phone use, and in one study it mediated the relationship between phone use and the severity of depression and anxiety. Separately, work on fear of missing out found it was highest in people whose needs for competence, autonomy and relatedness were least met, and that it mediated the path from those unmet needs to social media use.

For some people the phone is the problem. For others it's how they're coping with something else, and blocking it takes away the coping without touching the cause. Section 10 is about telling which one you are.

3. Why willpower is the wrong lever

The strongest single result in this area is a null one and it's barely reported. A preregistered trial of 787 university students had the intervention group write up to three action plans and three coping plans for cutting phone use. That's textbook implementation intentions, the advice in almost every article on this subject. Three weeks later there was no significant reduction against control.

Now put that next to the head-to-head that did work. Greyscale, an environmental change needing no resolve at all, produced an immediate measured drop. Goal-setting produced a smaller and slower one. And next to the field study of 42 digital wellbeing apps, where device-wide timers were snoozed 97.81% of the time, device-wide blockers were snoozed in five instances out of five, and every phone and app blocker in the study got deleted before it finished.

The general principle comes from Duckworth, Milkman and Laibson's review of self-control strategies: it's easier to prevent an impulse than to override one, and situational strategies beat cognitive ones. Their aside is a good one. People undervalue environmental fixes because they work, and there's no visible struggle to admire afterwards.

4. The setup, step by step

Roughly in order of evidence strength. You don't need all of it. Two of these done properly beats eight for a week.

Step 1. Get the real number, then stop watching it

Read your daily average and pickup count off Screen Time (iPhone: Settings, Screen Time) or Digital Wellbeing (Android: Settings, Digital Wellbeing). Write it down. You'll want it in three weeks and your memory of it will be wrong.

Then stop checking it every day. A longitudinal study of 242 people plus an online experiment found screen-time tracking improves awareness and is unlikely to reduce use. It also found people prefer tracking over blocking while rating tracking as less effective, and that preference was strongest among the heaviest users. Monitoring feels like doing something about it.

Step 2. Batch your notifications. Don't turn them all off.

This is the clearest reversal of standard advice in the literature. A randomised field experiment with 237 people compared normal notifications, batched three times a day, batched hourly, and off entirely. Batching three times a day won on everything measured: inattention, concentration, productivity, stress, mood, phone unlocks and sense of control, all at medium-to-large effect sizes.

Turning notifications off entirely backfired. Anxiety went up (d = 0.56), fear of missing out went up (d = 0.59), and there was no attention benefit. People with the silent phone spent the freed attention wondering what they were missing.

Three a day is also the number that worked in a separate email study. 124 adults checking email three times a day with the client closed reported significantly lower stress than checking freely. They only got down to about five checks a day rather than three, and got the benefit anyway, which is worth knowing if you're the sort of person who abandons a rule you've broken.

Sort every app into three tiers.

• Interrupt me. Calls from favourites, your partner, anyone who depends on you, imminent calendar alerts, two-factor codes. This list should be embarrassingly short.
• Deliver on a schedule. Email, team chat outside hours, news, group threads.
• Off. Every like, follow, tag, reaction, "someone posted for the first time in a while", memories, streak reminder, delivery promotion and app-store nag. The test: if the sender profits from your attention, it isn't a notification, it's an advert.

iPhone. Settings, Notifications, Scheduled Summary, on. Add your tier-two apps and set three delivery times. 8am, 1pm and 6pm works. Apps left out keep coming through immediately, which maps onto tier one without any extra work. Turn off Show Previews for tiers two and three while you're there, and turn off Badges.

Android. There's no native scheduled summary. Set tier-two apps to Silent (Settings, Notifications, the app, the channel, Silent) so they arrive without a sound or banner, turn off the notification dot, and use Modes or Do Not Disturb to open specific windows.

Re-audit every few months. Apps re-request permission after updates and new installs default to on.

Step 3. Put a binding daily limit on two or three apps

Not all of them. The wellbeing-app field study found the one thing that survived contact with real users was app-specific blocking of social media. The device-wide version was circumvented every time.

Pick the two or three that eat your day. You already know which. Give each a daily allowance you'd be content with rather than an aspirational one, because a limit you break every day teaches you the limit is decorative.

In Otto that's a budget rule. Choose the apps, give them minutes, and the timer counts down while you use them and resets in the morning. What makes it a limit rather than a suggestion is step 5.

Step 4. Turn the screen grey

Greyscale is the best-evidenced single setting change and it's modest. Four independent studies land on roughly 20 to 38 minutes a day less use: 20 minutes in a preregistered Android study, 28 in a crossover trial of medical students that held across both orders, around 38 in an undergraduate study.

Be clear about what it does. In the preregistered study the number of unlocks didn't change at all. Sessions got shorter, the reach for the phone was untouched. It didn't reliably improve sleep or productivity, and about a third of people said they wouldn't keep it on long term. Colour is a big part of what makes an icon grid and a photo feed rewarding, so removing it makes the phone duller once you're in. It does nothing about why you picked it up.

Pair it with something that targets pickups, and keep an escape hatch. Every study with decent retention had one.

iPhone. Settings, Accessibility, Display & Text Size, Colour Filters, on, Greyscale. Then Settings, Accessibility, Accessibility Shortcut, tick Colour Filters, and a triple-click of the side button gets colour back for maps, photos or anything colour-coded.

Android. Settings, Accessibility, Colour and motion, Colour correction, Greyscale, and turn on the shortcut. Or schedule it under Settings, Digital Wellbeing, Bedtime mode, Grayscale.

Otto has this as a rule of its own, so the screen goes grey when you open an app you've picked and comes back when you leave it, instead of being all-or-nothing across the phone.

Step 5. Lock it, once you trust the rules

Everything above is undone by a two-tap bypass. This is where most attempts die, and the snooze figure says so: 97.81%.

The options, in order of teeth:

• A delayed lock. Set your rules, live with them for a week or two, then lock the settings so changing them isn't something you can do in the moment. Otto calls this strict training. Ten days of ordinary use, then you can lock it. The delay is there because a locked bad rule is worse than no rule.
• A passcode you don't know. Have someone else set your Screen Time or Digital Wellbeing passcode and not tell you. That turns a two-tap undo into a conversation, which is real friction.
• A time-locked container for defined periods.

What doesn't count: announcing your intention. The evidence for declaring a goal is weak, and the 787-person planning trial found writing the plan changed nothing. Give up a control rather than making a statement.

Step 6. Close the browser leak

Block an app and the website is one tap away. Any setup that leaves a browser open leaks, and this is the most common reason things quietly stop working in week two.

iPhone. Settings, Screen Time, Content & Privacy Restrictions, Allowed Apps & Features, turn off Safari. It hides rather than deletes. Remember every other browser you've installed or the block is cosmetic.

Android. Digital Wellbeing app timers on the browser, or a blocker for a hard version.

The strongest version of this in the literature is worth knowing about even if you won't do it. The largest effects came from blocking all mobile internet for two weeks while leaving calls and texts working, which turns a smartphone back into a phone. That trial found big improvements in mental health (dz = 0.56) and wellbeing (dz = 0.45), a measurable gain in sustained attention, and 17 extra minutes of sleep a night. It also found that only 25.5% of participants kept the block running for 10 of the 14 days, in a sample who had volunteered because they wanted to cut down. Both halves of that are true at once.

Step 7. Set hard windows, and make them physical

A daily budget handles quantity. It does nothing about the two hours that matter most for most people, which are the last one before bed and the first one after waking.

Set a window where the apps don't open. Otto calls this a hard rule, with a start, an end and the days it runs. iPhone Downtime and Android Bedtime mode do a softer version. Then back it with the physical change, because a software block on a device in your hand is negotiable.

• Move the charger out of the bedroom tonight. The cable is the intervention and the phone follows it. This isn't separately proven, but it's how the tested restrictions were actually enforced, and it takes the decision out of the hands of a tired person at 11pm.
• Buy a cheap alarm clock. No evidence of its own. Its job is to remove the most legitimate-sounding reason to keep the phone by the bed.
• Deal with the emergency objection properly or you'll abandon this in week one. Leave the phone outside the bedroom on a Sleep focus with favourites allowed and repeated calls on, so a second call from the same number within three minutes rings through.
• Give the phone a parking spot at home. A bowl, a shelf, a drawer. The claim here is modest: a phone across the room gets picked up less often. Don't believe anyone who tells you a switched-off phone on your desk measurably drains your working memory. That famous 2017 result has failed two preregistered replications and the meta-analysis puts the real effect at about a tenth of the headline.

Step 8. Decide what you're doing instead, and put it within reach

People skip this step and it's the one carrying the wellbeing effect. The mediation analysis of the mobile internet trial found the gains ran through offline activity, social connectedness, self-control and sleep, not through absence. Take the phone away, fill the space with nothing, and you may just end up lonelier. Several studies in the detox review found exactly that.

Four rules that make a substitute get used:

• It has to already be there. The phone's advantage is that it's in your hand. A book in another room loses. A book on the arm of the chair competes.
• It should occupy your hands. Scrolling is a hands-idle behaviour. Instruments, knitting, cooking, drawing, puzzles and repairs compete with it directly. A podcast doesn't.
• Match it to the moment, not the day. Two minutes in a queue needs a different answer from ninety minutes after dinner.
• Commit the object, not the intention. The planning trial says writing "I will read more" does nothing. Putting the book on the pillow is an environmental change, and that's the category that works.

One trial makes the case cleanly. 642 people were randomised to cut social media by 30 minutes a day, add 30 minutes of exercise, do both, or neither. At six months the combination group had the largest and most durable gains, with depressive symptoms going from 4.6 to 2.9 against a control group that got slightly worse. A modest cut with a replacement beat a bigger cut alone.

5. Sleep

A randomised trial of 38 poor sleepers asked them to avoid the phone for 30 minutes before bed for four weeks. Sleep onset latency fell 12 minutes, total sleep time rose 18 minutes, pre-sleep arousal fell, and mood and working memory improved. Small pilot, but the direction matches the 17 extra minutes a night in the much larger internet-blocking trial.

Note the mechanism they measured, which was arousal. You're not lying awake because of photons. You're lying awake because you read something activating, or because the scroll ate the hour you were going to sleep in.

Which is why most of the blue light advice is wrong. A study comparing Night Shift on, Night Shift off and no phone found the night mode made no difference to sleep. The meta-analysis of blue-blocking glasses covers twelve studies with 6 to 21 participants each. The objective sleep efficiency effect crosses zero, the self-reported effects are much larger than the measured ones, which is the signature of expectation, and the strongest results are in clinical populations rather than general readers. Night modes are harmless. They aren't a sleep intervention and they don't substitute for putting it down.

Start at 30 minutes, because that's the number that was tested and it's easy to keep. Extend to an hour if it sticks. A 30-minute rule you keep every night beats a two-hour rule you give up on.

6. When your job is on your phone

The most useful finding here is counterintuitive. Research on after-hours email found the exhaustion is driven by the expectation of availability rather than the time actually spent. Anticipating a demand that might arrive depletes people on evenings when nothing arrives. The related construct, workplace telepressure, predicts poorer recovery, worse sleep and burnout.

So the highest-value move isn't a phone setting. It's stating a boundary and publishing it. "I reply within four working hours, call me if it's faster than that." That removes the anticipatory stress even when the workload is identical.

Then separate work from the rest of the phone.

• iPhone Focus Filters. A Personal focus can hide the work mail account and work calendar entirely, so outside hours the work inbox doesn't exist even though the app is installed. It's the most useful underused setting on the device.
• Android work profile. If your employer uses Android Enterprise the whole profile pauses with one toggle.
• Keep the channel, cut the feed. Keep email and team chat, remove news and social. That's the design that produced the largest measured effects.

7. What to expect

Numbers, so you can calibrate against something other than a marketing page.

Three caveats that apply to all of it. Nearly every trial recruits people who already wanted to cut down. Most outcomes are self-reported mood scales, and blinding is impossible when the intervention is a grey screen. Samples are overwhelmingly university students in wealthy countries with healthy baselines.

On timing: in a 1,039-person study of on-screen friction the steepest behaviour change happened within the first 21 days, and effectiveness then decayed as people got used to it. One participant put it as "my brain has gotten used to the waiting." Expect the first days to feel bad, and expect your setup to lose its bite after a few months. Both are normal. Rotating an intervention, or pausing and resuming it, restored the effect for about a quarter of that study's participants.

On how long any of this takes to become automatic: the 21-day figure is a myth with nothing behind it. The best real-world study found a median of 66 days, but that median covers fewer than half its participants, the observed range ran from 18 to 254 days, and the behaviours were simple ones like eating fruit at lunch. Two to eight months is the honest answer.

8. When you slip

You will. The relapse-prevention model developed by Marlatt and Gordon separates a lapse, meaning one violation, from a relapse, meaning abandoning the goal. Its central claim is that what decides which one you get isn't the lapse, it's your reaction to it. The model comes from substance-use research and hasn't been tested on phone use, so this is a transfer by analogy.

Two things drive a lapse into a relapse.

• The explanation you reach for. "I have no self-control, I'm addicted" is internal, permanent and global, and it predicts giving up. "I was exhausted after that meeting and the phone was in my hand" is situational, and people who reach for that adjust and carry on.
• Shame. Guilt is an unpleasant state and the phone is a reliable way to escape unpleasant states, so beating yourself up after a slip mechanically feeds the next one.

In four experiments a self-compassion prompt beat both a self-esteem boost and nothing at all on motivation to improve after failure. In the cleanest of them, people who got the self-compassion prompt after failing a test then studied for 306 seconds against 230 and 203. And the habit-formation study found, in its own words, that missing one opportunity to perform a behaviour did not materially affect habit formation. One bad evening isn't a broken habit.

Practically:

• Resume at the next natural boundary, not on Monday. The clean-start impulse turns a twenty-minute lapse into a five-day one.
• Ask what the situation was rather than what's wrong with you. The recurring high-risk ones are bad mood, conflict, social pressure, celebration, and testing yourself: "I'll just check quickly to prove I can."
• If you break the same rule every night at 10pm on the sofa, that's a design problem and not a character problem. Change the 10pm sofa.

9. What happened to people who tried

Every account here is published and attributable, and each one says whether it was measured or self-reported. There are no testimonials on this page. The group numbers sit next to the dramatic individual ones on purpose, because if you read only the dramatic ones you'll set yourself an expectation almost nobody meets.

The dramatic individual case

New York Times tech columnist Kevin Roose spent 30 days in 2019 cutting his phone use with help from Catherine Price. He put a rubber band round the phone as a speed bump, replaced his lock screen with three questions ("What for? Why now? What else?"), deleted social, news and games, bought a locking safe for it overnight, and took up pottery. He reported going from about five hours a day to just over one, and from more than 100 pickups to around 20.

That's self-tracked, it's one person, he had a coach and a newspaper watching him, and there's no published follow-up. It shows the thing is possible. It isn't a forecast.

The number that keeps everyone honest

In 2015 WNYC ran Bored and Brilliant, a week of daily challenges with usage measured through tracking apps rather than self-reported. Around 20,000 people finished it. 90% reduced their usage. The average reduction was six minutes a day.

Almost everyone who tries something moves the number. The average movement is small.

The one where structure beat willpower

Harvard Business School's Leslie Perlow ran an intervention at Boston Consulting Group where teams collectively guaranteed each member a scheduled, genuinely disconnected block of time off each week. Not individual resolve, a team obligation. It spread to over 900 teams in 30 countries.

Surveyed against non-participating teams: 51% against 27% excited to start work, 72% against 49% satisfied with the job, 54% against 38% satisfied with work-life balance, 58% against 40% seeing themselves at the firm long term. Client outcomes didn't suffer. It's the only intervention here that produced durable change at scale, and the only collective one.

The one with the cleanest measurement

1,661 people were paid to deactivate Facebook for four weeks before the 2018 US midterms, with the deactivation verified. It freed about an hour a day, increased time with friends and family, and raised subjective wellbeing by 0.09 standard deviations, which the authors put at roughly a quarter to two-fifths of the effect of therapy.

The durable part: nine weeks after it ended the treatment group was still using Facebook about 12 minutes a day less, and 5% had left their accounts deactivated. A month off permanently changed the behaviour of a minority. People's stated valuation of the platform also dropped after they'd lived without it, so they'd been over-valuing it from the inside.

The failure, which is the most useful one

Verge writer Paul Miller left the internet entirely for a year in 2012. He came back and wrote that he'd been wrong. Total abstinence produced isolation and loneliness instead of the restored self he'd expected, and he concluded the internet was mostly social rather than a distraction machine to escape from.

That matches the trial data. Abstinence has a pooled effect on mood and life satisfaction of about zero. Reduction with substitution is what works.

What people say in the research

A 2025 study followed 15 Instagram users aged 19 to 27 through diaries and interviews. Participants described regaining control ("I'm wasting one hour of my day just scrolling") and lower stress ("I didn't see it. And had like a more focus on myself. And that like really cut my stress off"). They also described craving ("my hand really wants to scroll"), and the authors documented a boomerang where some returned to previous levels or overconsumed catching up.

A peer-reviewed analysis of 94,358 posts and comments from the r/NoSurf community found members converge on three strategies: substituting hobbies and routines, using self-control tools, and changing the situation, meaning dumbphones and storing the phone away from the bed. They also overwhelmingly reject total disconnection as unworkable and aim for deliberate partial use.

One more, because it complicates things usefully. A case series of ten undergraduates found 8 of 10 improved on problematic-use scores and all reported feeling better, but the screen time reductions were inconsistent and didn't correlate with feeling better. People felt better without necessarily using their phones less. Whatever is being fixed here, it isn't only the minutes.

10. When this guide is not the right help

A screen-time app is a reasonable tool for a habit. It isn't a treatment for depression, anxiety, ADHD, gambling or trauma, and using one instead of getting help delays the help. The more common clinical picture by far is heavy phone use as a symptom of something else rather than a problem of its own.

Talk to a GP or a mental health professional if any of these apply. They're about impairment and risk rather than hours, because screen time on its own is a poor indicator.

• It is repeatedly costing you work, study or caring responsibilities.
• It is materially damaging a relationship, or someone close has raised it more than once and you have concealed or played down your use.
• You've tried to cut down, repeatedly, over months, and not managed it.
• You are losing significant sleep to it with daytime consequences.
• You use the phone while driving despite intending not to. That's the highest-harm behaviour in this whole subject and it's worth acting on today.
• The phone is the vehicle for something else. Gambling or sports betting is a recognised disorder with effective treatment and it's urgent. So is gaming that fits the ICD-11 pattern, compulsive pornography use, or spending you can't control.
• You're using it mainly to numb or escape distressing feelings rather than for anything you wanted.
• Your attempts to cut down have turned rigid or punishing. Obsessive tracking, harsh self-punishment for slips. That can shade into a different problem.

Some things outrank the phone question entirely. Persistent low mood or loss of interest lasting two weeks or more, anxiety that's limiting what you do, withdrawing from people, or drinking more alongside it. Those need a person, not a setting.

If sleep is the core of it, ask specifically about CBT for insomnia. It's the first-line treatment and it outperforms general sleep hygiene advice.

The short version

1. Read your real number off the phone, then stop watching the dashboard.
2. Batch notifications three times a day. Do not turn them all off.
3. Put a binding limit on two or three apps, one you can't dismiss.
4. Turn the screen grey and keep a one-gesture way back to colour.
5. Lock the settings once the rules are right, not before.
6. Close the browser leak.
7. Move the charger out of the bedroom tonight, and buy an alarm clock.
8. Decide what you're doing instead and put it physically within reach.
9. Expect 20 to 40 minutes a day rather than a transformation, and expect to rebound if you treat it as a challenge instead of a permanent setup.
10. When you slip, resume tonight, not Monday.

Otto does steps 3, 4, 5 and 7

A daily budget per app. A hard window where they don't open at all. Greyscale on the apps you choose. And after ten days, the option to lock the settings so the rule holds when you'd rather it didn't. Free on both stores, no account, no paid tier, and your usage never leaves your phone. There's a tip jar in the settings and that's the whole business model.

It covers four of the steps with the best evidence behind them. It doesn't do desktop, websites, accountability partners or analytics, and steps 1, 2, 6 and 8 are settings and furniture rather than an app. Nothing on this page requires Otto.

References

Everything cited above, in the order it appears. Where a claim has no reference the text says so.

1. World Health Organization. ICD-11, Disorders due to addictive behaviours. American Psychiatric Association, Internet Gaming Disorder (Section III, conditions for further study).
2. Panova, T. & Carbonell, X. (2018). Is smartphone addiction really an addiction? Journal of Behavioral Addictions 7(2).
3. Parry, D. A. et al. (2021). A systematic review and meta-analysis of discrepancies between logged and self-reported digital media use. Nature Human Behaviour 5.
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26. Brigham Young University / Sleep Health. Night Shift and sleep outcomes: no effect.
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28. Böttger, F., Poschik, M. & Zierer, K. (2023). Does the brain drain effect really exist? A meta-analysis. Behavioral Sciences. Pooled g = −0.14. Original: Ward, A. F. et al. (2017), JACR 2(2); failed replications: Hartmann et al. (2020), Ruiz Pardo & Minda (2022).
29. Dwyer, R. J., Kushlev, K. & Dunn, E. W. (2018). Smartphone use undermines enjoyment of face-to-face social interactions. Journal of Experimental Social Psychology 78.
30. Belkin, L., Becker, W. & Conroy, S. A., on after-hours email expectations; Barber, L. K. & Santuzzi, A. M. (2015). Please respond ASAP: workplace telepressure and employee recovery. Journal of Occupational Health Psychology.
31. Haliburton, L. et al. (2024). A longitudinal in-the-wild investigation of design frictions to prevent smartphone overuse. CHI '24. n = 1,039, mean 13.4 weeks.
32. Lally, P., van Jaarsveld, C. H. M., Potts, H. W. W. & Wardle, J. (2010). How are habits formed. European Journal of Social Psychology 40(6). Median 66 days for 39 of 82; range 18–254.
33. Marlatt, G. A. & Gordon, J. R. (1985). Relapse Prevention. Guilford. Collins, S. E. & Witkiewitz, K. (2013). Abstinence violation effect. Encyclopedia of Behavioral Medicine.
34. Breines, J. G. & Chen, S. (2012). Self-compassion increases self-improvement motivation. Personality and Social Psychology Bulletin 38(9).
35. Roose, K. (2019). Do not disturb: how I ditched my phone and unbroke my brain. The New York Times, 23 February.
36. Zomorodi, M. / WNYC (2015). Bored and Brilliant. Results tracker and TED talk. NPR reported ~18,000 participants and a four-minute average; Zomorodi's TED talk gives 20,000 and six minutes.
37. Perlow, L. A. (2012). Sleeping with Your Smartphone. Harvard Business Review Press; HBS Working Knowledge summary of the BCG Predictable Time Off results.
38. Allcott, H., Braghieri, L., Eichmeyer, S. & Gentzkow, M. (2020). The welfare effects of social media. American Economic Review 110(3).
39. Miller, P. (2013). I'm still here: back online after a year without the internet. The Verge, 1 May.
40. Lemahieu, L. et al. (2025). Meta-analysis of social media abstinence and wellbeing. Scientific Reports. 10 studies, N = 4,674; pooled effects ≈ zero.
41. Scheppe, J., Seiffen, L. & Berndt, A. (2025). Exploring the digital detox journey among Generation Y Instagram users. Information Technology & People 38(8).
42. Parry, D. A., Kuit, D., Murray, J. & van der Westhuizen, H.-M. (2025). r/NoSurf: a mixed-methods analysis. New Media & Society. 94,358 observations.
43. Kent, S., Masterson, C., Ali, R., Parsons, C. E. & Bewick, B. M. (2021). Digital intervention for problematic smartphone use in undergraduate university students. International Journal of Environmental Research and Public Health 18(24).
44. Burnell, K. et al. (2025). The effects of social media restriction: meta-analytic evidence. SSM – Mental Health 7. 32 RCTs, 5,544 participants, g = 0.17.

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