What research says about blocking an app instead of resisting it

· 5 min read

When you want an app, you can try to hold back, or you can have arranged things so that the app isn’t there. Angela Duckworth, Tamar Gendler and James Gross call the second kind a situational strategy. In a 2016 review they argue that earlier intervention is best as a rule, because an impulse is weaker when it is just starting. They also say that the advantage of situational strategies has “yet to be established empirically.”

The student experiments

Duckworth and colleagues then ran two field experiments, one with 126 boarding-school students and one with 159 University of Pennsylvania undergraduates. Everyone set a study goal for the coming week. One group was told to change their surroundings to remove temptations, and at the school the examples included installing apps that block sites like Facebook. A second group was told to practice resisting temptation when it came up. A third only set the goal.

A week later the first group reported more progress. Measured as Cohen’s d, a standard size for a difference between groups, the gap was 0.56 against the other two groups at the school. At the university it was 0.60 against the resisting group and 0.63 against the goal-only group. Resisting did no better than setting a goal alone (d = 0.01).

The authors call these effects large, and they list the limits. Progress was self-reported, using single questions. It was measured after one week and never again. Half of the students enrolled at the school didn’t finish the follow-up. Participants may also have answered as they thought the researchers wanted, though the authors think that unlikely.

App limits in a large experiment

Hunt Allcott, Matthew Gentzkow and Lena Song ran a randomized experiment with about 2,000 American adults on Android phones, published in 2022. One group could set a daily limit for each app in the study’s own phone app, with changes taking effect the next day. Over 12 weeks, that group spent 22 minutes a day less on social media, web browsers and YouTube than the control group, or 16 percent. The gap was still 19 minutes in the final week, and 78 percent were still using limits that cut into their normal use.

The result has clear limits. About half of the saved time, 12 minutes a day, moved to other apps. The effect on well-being was 0.04 standard deviations and not statistically significant, though people reported small drops on a smartphone addiction scale. Most participants could snooze their limits, and the paper doesn’t report the group without a snooze separately. The study ran at the start of the pandemic, with people who chose to join and who don’t represent US adults. The authors also expect a smaller effect without the survey steps that walked people through setting limits. The paper’s best-known figure, that self-control problems cause 31 percent of social media use, comes from an economic model and depends on its assumptions.

Blocking the whole mobile internet

A 2025 trial by Noah Castelo and colleagues asked 467 American and Canadian iPhone users to block all mobile internet for two weeks, leaving calls and texts alone. In those weeks the first group improved, with effect sizes (Cohen’s dz) of 0.46 for well-being, 0.57 for mental health and 0.24 for an attention test, while the group waiting its turn showed no change. Reported screen time fell from 314 minutes a day to 161 and came back to 265 once the block was optional.

Keeping the block on was hard. Of the 467, 266 set it up, and 119, or 25.5 percent, met the study’s definition of keeping it in place. Participants knew what the study was about, 83 percent were already motivated to cut down, and the comparison group got no alternative treatment, so expectations may explain part of the result. This is one study, and it blocked everything online, where Offhours blocks the apps you pick.

Commitment devices

A commitment device limits your future options or attaches a penalty to them. Duckworth, Katherine Milkman and David Laibson review the field and report mostly positive results. In one study they describe, 13.5 percent of smokers offered a deposit they would forfeit on a failed test passed it after six months, against 10 percent of those not offered it. The same review notes that almost no research directly compares different kinds of strategy.

Commitments can also backfire. In a savings experiment in the Philippines, Anett John found that average savings rose, yet 55 percent of clients defaulted and lost money. She suggests the penalties people chose for themselves were too low to hold them. That study is about money, and it doesn’t show that the same happens with phones.

What this means for a block

A block in Offhours is a situational strategy: you set it ahead of time and iOS holds it. No study has tested Offhours, which is still being built, so we can’t tell you what it will do for you.

The research does suggest how to use one. Set it up when you aren’t tempted. Choose a block you can keep on. In the 2025 trial, most people didn’t. If your time moves to another app, add that app. Duckworth and her coauthors also note, writing about stress, that dealing directly with a problem may work better in the long run than avoiding it.

Sources