Smartphones are powerful and versatile tools, but they can be dangerously addictive too: we've all know the sinking feeling when we realise we've been looking at Twitter for an hour and it's long past time to be asleep. The problem can be far more serious when kids are involved, and many parents would love to be able to impose more effective controls on their offspring's use of iPads and iPhones.

Both groups will be pleased to hear that iOS 12, the upcoming update to Apple's mobile operating system announced at WWDC 2018, adds a range of tools for monitoring and limiting device usage on a per-app basis. There are updates affecting notifications and expanding the capabilities of Do Not Disturb, but in this article we're going to focus on the powerful features of Screen Time.

Monitoring app usage

Screen Time covers a range of features, but these can be divided into two main categories: monitoring and limiting.

Every week you will receive a report detailing how much you've used your iPhone or iPad over the past seven days. In the popup summary you'll see a daily average usage time (and whether this is up or down on the previous week, and by how much), the average time between pickups, the average daily number of notifications.

How to set app limits with Screen Time for iPhone & iPad: Summary report

Screen Time divides each day's usage into a bar chart colour-coded for social media, entertainment and other categories, and showing the most-used apps. And there's a section called Insights that offer observations that it feels will be useful.

You can tap through from the summary to see more details. You'll be shown graphs of daily usage, the length of your longest session, and the amount you've used your device after bedtime, which is likely to be particularly problematic. And the per-app information gets more detailed too, listing which ones are causing the most pickups and sending the most notifications.

How to set app limits with Screen Time for iPhone & iPad: Weekly activity summary

All of this is valuable information for analysing ways in which your device usage is becoming unhealthy - and the specific apps and types of use that need to be limited - but also giving you targets for improvement.

Limiting your own app usage

When we were looking at the detailed tap-through report just now, you'll have noticed that each app on the most-used list has a sand-timer icon next to it. If this is highlighted in orange, it means you've set a limit on that app's usage. (Limited apps will also appear in a separate category above most-used, labelled Limits.)

Tapping through to an individual app within Screen Time allows you to set a limit, customised by hours and minutes and potentially applied to specific days only. The limit doesn't only apply on this device, note - it will also apply on any other devices signed in to the same iCloud account.

Screen Time will pop up a notification when you've got five minutes left of your daily usage limit, and this may be enough for some people to take the hint and quit.

How to set app limits with Screen Time for iPhone & iPad: Time limit

But for those of us with less self-control, it may be useful to set the toggle Block At End of Limit to on, which means the app won't work at all once the time is up.

This last option is particularly important if you're setting limits for kids (who will be able to ask you for an extension when they run out of time).

Limiting your kids' app usage

If you've got Family Sharing set up, Screen Time will know to send a weekly activity summary to your kids, but to also send a summary of your kids' activity to you, so you can keep an eye on what they've been up to.

You can create what Apple calls Allowances for your children's app usage, and this is more sophisticated than iOS parental controls in the past. And it's all set up from your parental device.

How to set app limits with Screen Time for iPhone & iPad: App limits for kids

You can schedule Downtime, when the child must be away from their screen. Among the Downtime options, you'll see options to set a start and end time, and to block device access at the scheduled Bedtime.

How to set app limits with Screen Time for iPhone & iPad: Downtime

Like the app limits discussed earlier, Downtime sends a notification when five minutes is left, and allows users to ask for more time. (You'll have to okay this.)

You can also set time limits for individual apps, and limits on types of app (such as games, social networking and health & fitness) or content (by age rating, for example).

Finally, you can specify apps that should always be allowed, such as the Phone app or educational apps.

More in-depth advice for parents can be found in our article How to set up parental controls on iPad & iPhone.