Comparison

World Timezone Calendar vs ONE WATCH

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

World Timezone Calendar

Easily schedule meetings and events across different time zones. This app helps you find the perfect time for global coordination by comparing multiple time zones and integrating with your existing calendar. Plan ahead with future time views and share events that automatically adjust to recipients' local times.

Highlights
  • Cross-timezone scheduling
  • View calendar in multiple timezones
  • Time travel to plan ahead
  • Add unlimited timezones
  • Day/night indicators
  • Home screen widget
  • Global event sharing
Features
Read full description

Coordinate global meetings, calls, and events without the timezone math. Standard world clocks only tell you what time it is right now. World Calendar goes further: it’s a powerful timezone converter and international meeting planner that lets you look into the future to find the perfect time for everyone. Whether you are scheduling a global team sync, planning an international trip, or calling family overseas, World Calendar integrates directly with your iOS Calendar to make cross-timezone scheduling effortless. CROSS-TIMEZONE SCHEDULING Compare multiple timezones side-by-side to instantly pinpoint the ideal meeting time. Tap anywhere to set a target time, and tap twice to seamlessly create an event directly in your calendar. VIEW YOUR CALENDAR IN MULTIPLE TIMEZONES World Calendar displays your existing events across all your selected timezones. Create, edit, and share events with a single tap, ensuring your global schedule is always perfectly aligned. KEY FEATURES: • Time Travel: Scroll into the future to plan days, weeks, or months ahead. • No Limits: Add and compare as many timezones as you need. • Day/Night Indicators: Instantly see if your contact is awake or asleep. • Home Screen Widget: Check your favorite timezones at a glance without unlocking your device. • Watch Widget and App: Put your recently selected timezones on your wrist • Easy Search: Find locations by city name, timezone abbreviation (e.g., EST, GMT), or UTC offset. • Global Sharing: Send event invites to other users that automatically adapt to their local timezone. • DST Accuracy: Fully automatic adjustments for daylight saving time changes globally. • Nautical Time Zones: Full support for standard UTC offsets without DST adjustments. • Landscape View: Turn your device for a wider, comprehensive timeline view.

About

ONE WATCH

Features
Read full description

ONE WATCH shows you the local time, live weather, and the perfect moment to call - for everyone who matters to you. Across iPhone, iPad, Apple Watch, and home-screen widgets. +++ KNOW WHEN TO CALL A traffic-light indicator tells you in one glance: green when it's a good time, orange when it's borderline, red when it's the middle of the night. Set per-contact call windows, weekday availability, and time-zone preferences. +++ PHOTO WIDGETS Add your contacts with their real photo and see them on your home screen and Apple Watch. World clock, but personal. +++ LIVE WEATHER Each contact card shows the current weather at their location, powered by Apple Weather. Useful for travel planning, meeting coordination, or just being a thoughtful friend. +++ APPLE WATCH + COMPLICATIONS Full Apple Watch app with all complication slots — see your people on every watch face. +++ EVENT CONVERTER Plan meetings across time zones. Pick a moment, see what time it is for everyone. +++ 12 LANGUAGES English, German, Spanish, Portuguese, French, Italian, Dutch, Japanese, Korean, Chinese, Hindi, Arabic. +++ LIGHT & DARK MODE Beautifully designed for both — choose your preference or follow the system. +++ PRIVACY FIRST No accounts. No tracking. No analytics. No ads. Contact data stays on your device, never uploaded anywhere. Weather data is fetched via Apple WeatherKit. +++ ONE WATCH PREMIUM Unlock home-screen widgets, Apple Watch app + complications, multiple contact photos, weekday selector, per-contact availability toggle, and analog clock styles. Choose monthly, yearly, or a one-time lifetime purchase. Family Sharing supported. Privacy Policy: https://onewatch.onepage.me/privacy Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Made in Austria.

Screenshots

World Timezone Calendar4 screens
ONE WATCH4 screens

Verdict

The call

The clearest difference is ads: ONE WATCH at none against World Timezone Calendar's shown. ONE WATCH also leads on update cadence (every 3 days vs every 4 months). World Timezone Calendar's advantage is iOS requirement (16.6 vs 18.0). On price, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. World Timezone Calendar sells 1 one-off in-app purchase and ONE WATCH sells 3 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

World Timezone Calendar ships an update every 4 months, ONE WATCH every 3 days. The most recent releases landed on November 1, 2026 and October 31, 2026 respectively.

Scorecard3 real differences · 7 level
World Timezone Calendar versus ONE WATCH: the parameters behind the verdict, then further details
ParameterWorld Timezone CalendarONE WATCH
PriceFreeFree
Rating4.9 (315 ratings) — better—
Positive reviews76.5% of reviews—
Number of ratings315 — better—
Update frequencyEvery 4 monthsEvery 3 days — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, Mac, Apple Watch — betteriPhone, iPad, Apple Watch
Requires iOS16.6 — better18.0
Further details — not scored
Size19 MB52 MB
Age rating4+4+
DeveloperGeospike Pty LtdJohann Szebeni

Bugs and requests

World Timezone Calendar

Reported bugs

7 issues
  • 🐛 Inappropriate ads in free version
  • 🐛 Widget settings not saved
  • 🐛 Cannot add new events with double tap
  • 🐛 Timezone abbreviations not displayed
  • 🐛 Search feature doesn't work
Show 2 more
  • 🐛 Crashes when adding a city
  • 🐛 Widget expansion settings not saved

Requested features

5 requests
  • Add more cities
  • Option to freeze time zones for comparison
  • Switch between 24-hour and AM/PM clock
  • Cleaner design with better calendar event integration
  • Ability to pick a specific date to view

ONE WATCH

Not enough reviews yet to summarise bugs or requests.

In-app purchases

1 purchases

World Timezone Calendar

One-time1
  • Remove Advertising$19.95
3 purchases

ONE WATCH

Subscriptions2
  • Premium Monthly$2.991 Month
  • Premium Yearly$24.991 Year
One-time1
  • Premium Lifetime$99.99

Questions

Is World Timezone Calendar free?
World Timezone Calendar is free to download, with in-app purchases available.
Is ONE WATCH free?
ONE WATCH is free to download, with in-app purchases available.
Do World Timezone Calendar or ONE WATCH have ads?
World Timezone Calendar shows ads; ONE WATCH does not.
Which is updated more often, World Timezone Calendar or ONE WATCH?
World Timezone Calendar ships an update every 4 months, and ONE WATCH every 3 days. Most recently, World Timezone Calendar was updated on November 1, 2026 and ONE WATCH on October 31, 2026.

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