Change four things and leave the rest alone. Strip the home screen to tools you open on purpose. Silence every notification that isn't a person. Turn the display grey. Charge the phone in a different room from the one you sleep in. Below is the build, setting by setting, with the evidence attached where evidence exists.
Why the limits you set stopped working
You already tried the limit. You typed the passcode past it, probably in bed, probably within a fortnight. That isn't a character flaw. The limit asked the tired version of you to overrule the rested version, and the tired version had the code.
So the build below moves the effort. Each change is made once, while you're calm, and then keeps working without you deciding again. If your last attempt collapsed in an evening, [there's a piece on that](/guides/phone_screen/you-undid-all-the-settings-what-now).
The evidence here is thinner than most articles admit. All four UK Chief Medical Officers wrote that ["This research does not present evidence of a causal relationship between screen-based activities and mental health problems"](https://www.gov.uk/government/publications/uk-cmo-commentary-on-screen-time-and-social-media-map-of-reviews), and that "it could be, for example, that CYP who already have mental health problems are more likely to spend more time on social media". They still advise that "It is still wise to take a precautionary approach."
That's the register. Cheap changes, judged on what they cost you rather than on a promise.
The home screen
Page one is a shop window, and right now it's selling to you. Rebuild it as a toolbox.
- Keep what you open with an intention: camera, maps, messages, calendar, banking.
- Move everything you open out of boredom to the last page, in a folder, without a badge. Search still finds it in two seconds, and two seconds is two seconds of noticing.
- Empty the dock down to two icons. The dock is muscle memory, and a half empty one breaks the reach.
- No widget that updates. A widget with fresh numbers on it is a notification you volunteered for.
Eight minutes, and you won't want to redo it. That reluctance is the point.
Notifications
The default is that anything can interrupt you. Flip it, so interrupting has to be earned.
- Direct messages and calls from real people stay on. Everything else goes to silent delivery.
- Turn off badges for anything that isn't a person. The red dot turns a glance into a session.
- Group chats keep the messages and lose the sound. You'll read them once, not eleven times.
- Schedule a quiet period from an hour before bed until after breakfast, with calls from a short list allowed through.
- Every app asking permission on first launch gets a no. You can say yes later, and you almost never will.
Work apps are the argument here. If your job needs you reachable, keep the one channel it actually uses and silence the four others that only feel like work. On call is a rota with hours. If yours has no hours, that's a conversation with your manager rather than a settings problem.
Grayscale
Accessibility, then colour filters, then greyscale. Bind it to a triple-press of the side button so photos still work when you need them.
This is the one setting here with a controlled trial behind it. In a field experiment, grayscale, which the researchers call design friction, ["led to an immediate, significant reduction of objectively measured screen time compared with the control condition"](https://pubmed.ncbi.nlm.nih.gov/36577008/).
Now the part usually left out. From the same study: "In contrast to the popular belief that reducing screen time has broad benefits, we found no immediate causal effect of reducing usage on subjective well-being and academic performance." Fewer hours, yes. A better week, not promised.
Where the phone sleeps
Out of the bedroom. This is the single piece of advice the UK Chief Medical Officers give without hedging: "Sleep matters. Getting enough, good quality sleep is very important. Leave phones outside the bedroom when it is bedtime."
The supporting research is an association rather than proof, and it's about children. A review of 20 cross-sectional studies covering 125,198 children found ["a strong and consistent association between bedtime media device use and inadequate sleep quantity"](https://pubmed.ncbi.nlm.nih.gov/27802500/), odds ratio 2.17. The detail worth acting on: children who had access to a device at night, without using it, also slept worse.
Practically: charger in the hall, a cheap alarm clock, a book on the bedside table so your hand has somewhere else to go. [More on rebuilding the first and last hour](/guides/phone_screen/mornings-nights-and-getting-them-back).
One extra, if the four aren't enough
The strongest trial here blocked all mobile internet for two weeks, kept texts and calls working, and found it ["improved mental health, subjective well-being, and objectively measured ability to sustain attention; 91% of participants improved on at least one of these outcomes"](https://pubmed.ncbi.nlm.nih.gov/39967678/). Borrow the shape without the extremity: in mobile data settings, switch data off for the two or three apps that own you, so they only load on wifi. Calls and messages carry on, so nobody loses you.
The passcode trick, and why it half works
Set the screen time limit, then have someone you trust type the passcode and not tell you. It raises the cost of an override, and plenty of people get a useful month out of it.
The weakness is obvious once you say it out loud. You can reset the phone. Or ask them for the code at eleven at night, and they'll give it to you, because saying no to someone you love is hard. If you want friction that doesn't depend on a person picking up, [Shield](/shield) is the part of Renovyn that blocks across phone and laptop with a delay on switching it off.
What has evidence, and what doesn't
| Change | What's actually known | |---|---| | Grayscale | Reduced measured screen time in a randomised field experiment. No effect on wellbeing or grades in that trial. | | Blocking mobile internet | One randomised trial, two weeks, gains in attention, mental health and wellbeing for most participants. | | Phone out of the bedroom | Recommended by the UK CMOs. The sleep research behind it is cross-sectional and about children, so it shows association only. | | Notification batching and scheduled summaries | No efficacy trials we could find. People report it helps. | | A weekly offline day | No efficacy trials we could find. | | Dumbphones and flip phones | No efficacy trials we could find. Popular, plausible, unproven. | | Consumer blocking apps | No trials of the apps themselves. The blocking mechanism has one trial behind it. |
Every other article on this subject will tell you the last four rows change your life. Nobody has shown it.
Common questions
**Does grayscale really work, or is it a placebo?** It reduced objectively measured screen time in a randomised field experiment, so the effect on hours was measured rather than self-reported. The same study found no immediate improvement in wellbeing or academic performance. Expect it to change the pull of the screen.
**How do I stop bypassing my own screen time passcode?** You mostly can't on your own, because you're the one who set it. Give the code to someone else, or use a block with a cooling-off delay so the override takes long enough for the moment to pass.
**Will a flip phone fix this?** Maybe, and no trial says so. People who switch often report relief, then hit practical problems with banking, two-factor codes and work. A fortnight of grayscale plus a mobile data block costs nothing and tells you whether you'd cope.
**My job needs me on my phone. What can I actually change?** Keep the one channel your job really uses and silence the rest, including the ones that only feel like work. The charging place, the home screen and grayscale are untouched by your job.
Sources
- [UK Chief Medical Officers' commentary on screen-based activities and children and young people's mental health](https://www.gov.uk/government/publications/uk-cmo-commentary-on-screen-time-and-social-media-map-of-reviews), for no evidence of causation, the precautionary approach, and phones outside the bedroom at bedtime.
- [Digital Strategies for Screen Time Reduction: A Randomized Field Experiment, Cyberpsychology, Behavior, and Social Networking 2023](https://pubmed.ncbi.nlm.nih.gov/36577008/), for grayscale and the null result on wellbeing and academic performance.
- [Association Between Portable Screen-Based Media Device Access or Use and Sleep Outcomes, JAMA Pediatrics 2016](https://pubmed.ncbi.nlm.nih.gov/27802500/), for the 20 cross-sectional studies, 125,198 children, and access without use.
- [Blocking mobile internet on smartphones improves sustained attention, mental health, and subjective well-being, PNAS Nexus 2025](https://pubmed.ncbi.nlm.nih.gov/39967678/), for the two week block and the 91% figure.
