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What is AlarmKit, and why does it matter for calendar apps?

The iOS framework that finally lets an app schedule a genuine alarm instead of a notification, and what changed the day it arrived.

What is AlarmKit?

AlarmKit is the iOS framework, introduced with iOS 26, that lets a third-party app schedule a real system alarm. Before it, only Apple’s Clock app could do that, so everything else fell back on notifications. An AlarmKit alarm rings through Silent Mode and Focus, keeps ringing until dismissed, and fires with the app closed.

TL;DR

Before iOS 26, only the Clock app could create real alarms. AlarmKit opened that to third-party apps, which is why calendar alarm apps suddenly became possible.

For years, every app promising to wake you for a meeting was quietly limited to a notification. It could be loud when your phone was loud, and silent when it was not, and there was nothing developers could do about it. AlarmKit removed that ceiling.

What did apps have to do before AlarmKit?

They posted notifications and hoped. Some used critical alerts, which require a special entitlement from Apple and are intended for health and safety, so a meeting reminder rarely qualifies. Others played audio in the background, which iOS suspends. Every approach failed in the same situation: a phone on silent, which is precisely when you most need it. We go into it in sleeping through a morning meeting.

What did AlarmKit change?

An app can now hand the system a scheduled alarm, with a title and a time, and the system owns it from that point. The alarm rings at full volume through Silent Mode, Focus and Do Not Disturb, presents its own full-screen interface with stop and snooze, and keeps going until someone deals with it.

Crucially, it does not depend on the app. Once scheduled, the alarm survives the app being closed, swiped away, or not opened for a week, and it survives a restart. More on that in an iPhone alarm that did not go off.

What a calendar app could do before and after iOS 26.
CapabilityNotificationAlarmKit alarm
Rings on silentNoYes
Survives FocusNoYes
Keeps ringingNoYes
Works with app closedPartlyYes

The trade-off

AlarmKit requires iOS 26.1 or later, so an app built on it cannot support older iPhones. That is a real cost, and it is why calendar alarm apps that work on older versions are still using notifications. There is no version of this where you get both.

Why does it matter for a calendar app specifically?

A calendar alarm is only useful if it is reliable in the situation you set it for: phone face down, Focus on, app closed since Friday. AlarmKit is what makes that possible, and it is why the category exists now rather than three years ago. Pealo is built on it, which is why the iPhone app schedules real system alarms from your calendar instead of posting notifications.

Built on AlarmKit, from day one

Real system alarms from your calendar. Seven days free.

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FAQ

Questions about this article

What is AlarmKit?

An iOS framework introduced with iOS 26 that lets third-party apps schedule real system alarms rather than notifications.

Why do AlarmKit alarms ring on silent?

Because iOS exempts alarms from Silent Mode, Focus and Do Not Disturb by design, whichever app scheduled them.

Does the app have to be open?

No. Once scheduled, the alarm belongs to the system and fires with the app closed, and after a restart.

Which iOS version do I need?

iOS 26.1 or later. Apps built on AlarmKit cannot support older versions.

Are critical alerts the same thing?

No. Critical alerts are notifications with a special entitlement, intended for health and safety. AlarmKit alarms are genuine alarms.

The framework exists. So does the app.

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