iPhone · Google Calendar & Microsoft Outlook
Calendar Alarm App for Google & Outlook
Google Calendar and Outlook send notifications. Notifications disappear whether or not you act on them. A calendar alarm app does something different: it fires an alert that demands a response before it stops. OnTimer is that app — it connects to your existing calendars and fires an interruptive alarm for every event, automatically.
Free · Works with Google Calendar & Microsoft 365 / Outlook
Direct Answer
A calendar alarm app bridges the gap between your schedule and being interrupted at the right moment. Unlike a calendar notification — which informs without interrupting — a calendar alarm requires acknowledgment before it stops. OnTimer connects to Google Calendar and Outlook and fires these high-attention alarms automatically for every event, with no per-event setup.
Works With Your Existing Calendars
You don't switch calendars. You don't re-enter events. OnTimer connects to where your schedule already lives.
Google Calendar
Connect personal Gmail, Google Workspace, or both. Every event across all linked Google accounts gets an alarm automatically. Nothing to configure per event.
- ✓Personal Gmail
- ✓Google Workspace
- ✓Multiple accounts
Microsoft 365 & Outlook
Connect your work Microsoft 365 account or personal Outlook calendar. Teams meetings, client calls, internal standups — all covered.
- ✓Microsoft 365
- ✓Outlook Calendar
- ✓Multiple accounts
Why Calendar Notifications Aren't Enough
Standard calendar reminders — from Google Calendar, Outlook, or built-in iOS calendars — are delivered as notifications. And notifications have a fundamental limitation:
They disappear automatically
A notification banner vanishes after a few seconds whether you act on it or not.
They can be dismissed by accident
A quick swipe and the reminder is gone — even if you didn't consciously decide to ignore it.
They compete with everything else
Your phone shows dozens of notifications per day. Calendar reminders don't stand out.
They don't interrupt deep work
When you're focused, notifications fade into the background — especially with Focus mode on.
The Difference Between Reminders and Alarms
A reminder informs you. It appears, you acknowledge it (or don't), and it goes away.
An alarm demands action. It continues alerting until you respond. For meetings that matter, you want alarm behavior.
Who Benefits From a Calendar Alarm App
Professionals with back-to-back meetings
When every hour is scheduled, a single missed transition derails the rest of the day.
Remote workers
Without the physical cues of an office environment, it's easier to lose track of time.
People with ADHD or time blindness
Passive notifications often aren't strong enough to break through hyperfocus or time distortion.
Executives and salespeople
High-stakes meetings require showing up prepared and on time — every time.
Anyone managing multiple calendars
When Google Calendar and Outlook events are spread across accounts, it's easy for something to slip through.
How OnTimer Turns Your Calendar Into an Alarm System
Connects to your calendar
Links to Google Calendar and Microsoft Outlook — including multiple accounts.
Monitors your schedule
Automatically detects upcoming events and prepares alarms in advance.
Fires an interruptive alarm
Before each meeting, triggers an alarm that stays on your screen and requires an explicit dismiss or snooze before it stops.
No manual event entry. No configuration per meeting. Your calendar is the source of truth — OnTimer just makes sure you can't ignore it.
Frequently Asked Questions
What is a calendar alarm app?▾
A calendar alarm app turns your existing calendar events into persistent alarms — not passive notifications. Instead of a banner that disappears, you get an alert that stays on your screen until you dismiss it, similar to how your morning alarm works.
Does OnTimer work with Google Calendar?▾
Yes. OnTimer connects directly to Google Calendar — personal Gmail accounts and Google Workspace. Every event in your Google Calendar automatically gets a persistent alarm. No manual setup per event required.
Does OnTimer work with Microsoft Outlook or Microsoft 365?▾
Yes. OnTimer connects to Microsoft 365 and Outlook calendars. Work calendars, Teams meetings, and personal Outlook events all get persistent alarms. Multiple Microsoft accounts are supported.
What's the difference between a calendar notification and a calendar alarm?▾
A notification appears briefly and disappears automatically — whether you act on it or not. An alarm stays on your screen until you explicitly dismiss it. Google Calendar and Outlook send notifications. OnTimer turns those events into alarms.
Can OnTimer work with both Google Calendar and Outlook at the same time?▾
Yes. OnTimer supports multiple connected calendars simultaneously — you can link Google Calendar and Microsoft 365 at the same time, and alarms will fire for events from both.
Who benefits most from a calendar alarm app?▾
People who miss meetings despite having reminders set. Remote workers without physical office cues. People with ADHD or time blindness who need stronger transition signals. Anyone managing multiple calendars across Google and Microsoft.
Related Guides
- Why Calendar Notifications Fail (And What Actually Works) →
- Calendar Notifications Not Working? Why Reminders Fail — and What Fixes It →
- How to Turn Calendar Events Into Real Alarms →
- How to Make Calendar Reminders Persistent →
- Calendar Notifications vs Alarms →
- Why Calendar Reminders Fail →
- How to Never Miss a Meeting Again →
Try OnTimer
Replace passive notifications with alarms that actually work. Free download for iPhone. Works with Google Calendar and Microsoft Outlook.
Android coming soon — join the waitlist.