Batching Phone Notifications: What a Two-Week Experiment Found

Most phones deliver every notification the moment it arrives, at times nobody chose. A 2019 field experiment tested a simple alternative: let the notifications wait, and deliver them in batches at set times of day.

What the researchers did

Nicholas Fitz and Kostadin Kushlev, with Ranjan Jagannathan, Terrel Lewis, Devang Paliwal and Dan Ariely, published the study in Computers in Human Behavior in 2019. Fitz and Ariely worked at Duke University's Center for Advanced Hindsight and Kushlev at Georgetown University. The team built an Android app that could hold back a phone's notifications and release them on a schedule, and in March 2017 recruited smartphone owners living in India through Amazon Mechanical Turk.

For the first week, everyone received notifications as usual. For the next two weeks, each person was randomly assigned to one of four groups:

• notifications as usual, the control group;
• notifications in a batch every hour, on the hour;
• notifications in three batches a day, at 9 a.m., 3 p.m. and 9 p.m.;
• no notifications at all.

Anyone could still open an app to check it at any time. Every evening, participants answered a short survey about their day: attention, stress, mood, productivity, their sense of control over their phone and their fear of missing out. The app also counted how often they unlocked their phones. The analysis covered the 237 people who completed at least three quarters of the surveys, with an average age of 30.

What they found

• Three batches a day helped. Compared with the control group, people whose notifications came three times a day unlocked their phones less often and felt more in control of them. They reported less inattention, better concentration, less stress and more productivity, all differences of medium size, and their mood was a little better.
• Hourly batches barely helped. People in the hourly group felt less interrupted by notifications, but otherwise didn't differ from the control group.
• No notifications backfired. People who received none felt less interrupted too, but their attention didn't improve, and they reported more anxiety and more fear of missing out than the control group.
• Attention explained the gains. The benefits of three daily batches ran through lower inattention: by the authors' analysis, being interrupted less is what left people feeling less stressed and more productive. The three-batch group did feel more fear of missing out on notifications, but their well-being improved anyway.
• People misjudge their own notifications. Asked afterward, participants said they wanted about half as many notifications as they thought they received, and they greatly underestimated how many they actually got.

What the study can't tell you

The batching lasted two weeks, so the study can't say whether the benefits hold up, grow or fade over months. Almost every outcome came from a daily self-report survey, and the authors tested many outcomes without adjusting for the number of comparisons, so any single result deserves some caution.

The participants were Android users in India, recruited online, most of them men and many of them working in information technology, so the results may not carry over to everyone. And 108 people who signed up didn't complete the study, though they dropped out at similar rates in every group.

The schedule was also strict: the app controlled it, and participants couldn't change it. The authors suggest that this lack of control may be part of why getting no notifications at all raised anxiety instead of calming it.

What it means for your phone

You don't need a research app to try this. On an iPhone, Scheduled Summary (Settings, then Notifications) gathers the notifications of the apps you choose and delivers them at the times you set. Keep messages from people coming through, and let everything else arrive two or three times a day. Don't switch everything off in one go: in this study, total silence made people more anxious without sharpening their attention.

For the hours when you want the apps themselves out of reach, a Work, Focus or Reading session in Unrotten, started from Home's + button, keeps the apps you chose locked until it ends. For a full routine for an hour of focused work, read how to focus better, and for a related experiment, the phone notification study found that alerts cost attention even when nobody answers them.