Comparison

Underwater Stopwatch vs World Clock

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

Head to head
About

Underwater Stopwatch

Features
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A lightweight Apple Watch stopwatch and timer built for wet hands. Everything is controlled by rotating the Digital Crown, so you never need the touchscreen. It keeps working when your fingers are wet, gloved, or underwater, and while your watch is in Water Lock. TWO MODES Stopwatch counts up from zero, with laps. Timer counts down from any duration you set, drawn as a draining hourglass, with three unmistakable buzzes at zero. Run past zero and the overtime is recorded too. CROWN CONTROLS Rotate up to start, pause, and save. Rotate down to add a lap, or to continue a paused session. No taps, no buttons, nothing to fumble for. HAPTIC TIME CUES Set a repeating buzz at any interval, plus an optional stronger one for milestones. A light tap every 30 seconds and a firmer one every 5 minutes, for example. Track elapsed time without ever looking at your wrist. STAYS ON SCREEN The app holds the display for your whole session, so a glance shows your timer instead of the watch face. ON YOUR IPHONE Every session syncs across: full history, lap splits with faster and slower comparisons, and your average and longest times. Set durations and cues from either device. BUILT FOR Swimming and pool laps. Surfing. Cold plunges and sauna rounds. Breath-hold and apnea training. Anything you time where looking at a screen is not practical. PRIVATE BY DEFAULT No workouts. No fitness tracking. No Health data. No account, no subscription, no ads, no analytics. Every session stays on your devices.

About

World Clock

Features
Read full description

World Clock - Time Zones β€” Your all-in-one world clock & time zone converter Instantly check the current time zone anywhere in the world. Whether you're scheduling a meeting across US time zones, planning international travel, or keeping in touch with family overseas, this world clock app gives you accurate, live time zone information at a glance. WORLD CLOCK, MADE SIMPLE See the live time in every US time zone β€” Pacific, Mountain, Central, and Eastern β€” plus Alaska, Hawaii, and Atlantic time, all updating in real time. INTERACTIVE TIME ZONE MAP Explore a color-coded, interactive map for USA, North America, South America, Europe, Australia, and Asia. Tap any region to instantly see its current local time. TIME ZONE CONVERTER Compare time zones side-by-side β€” perfect for scheduling calls with remote teams, coordinating travel plans, or catching a live event happening in another part of the world. COORDINATED UNIVERSAL TIME (UTC) Always know the current UTC time, kept accurate and synced automatically. DEVICE CLOCK & DRIFT CHECK See your device's own local time with a clean analog clock display. 12-HOUR / 24-HOUR TOGGLE Switch instantly between 12-hour and 24-hour time formats to match your preference. KEY FEATURES: - Live world clock with real-time updates - Time zone converter for USA & international zones - Interactive, color-coded time zone map - Covers all major regions: USA, North America, South America, Europe, Australia, Asia - UTC / GMT time always visible - 12-hour and 24-hour display toggle - Clean, modern, easy-to-read design - Works for travel planning, remote work, global meetings & international calls PERFECT FOR: - Remote teams scheduling meetings across time zones - Travelers checking time zones before they land - Families and friends staying connected across countries - Professionals working with international clients - Anyone who needs to know "what time is it in..." β€” instantly Download World Clock - Time Zones today and never lose track of time again, no matter where in the world you (or your plans) are.

Screenshots

Underwater Stopwatch4 screens
World Clock4 screens

Verdict

The call

The clearest difference is update cadence: Underwater Stopwatch at every 3 days against World Clock's every 6 weeks. World Clock's advantage is iOS requirement (13.0 vs 18.0). On price, ads, in-app purchases and device support there is nothing between them.

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

CostPrice Β· In-app purchases Β· Ads Β· Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Underwater Stopwatch ships an update every 3 days, World Clock every 6 weeks. The most recent releases landed on October 25, 2026 and October 7, 2026 respectively.

Scorecard2 real differences Β· 4 level
Underwater Stopwatch versus World Clock: the parameters behind the verdict, then further details
ParameterUnderwater StopwatchWorld Clock
PriceFreeFree
Update frequencyEvery 3 days β€” betterEvery 6 weeks
AdsNoNo
In-app purchasesNoNo
DevicesiPhone, Apple WatchiPhone, iPod
Requires iOS18.013.0 β€” better
Further details β€” not scored
Size4 MB38 MB
Age rating4+4+
DeveloperVlad TopalaBhavin Harsoda

In-app purchases

None

Underwater Stopwatch

No in-app purchases

None

World Clock

No in-app purchases

Questions

Is Underwater Stopwatch free?
Underwater Stopwatch is free to download, with no in-app purchases.
Is World Clock free?
World Clock is free to download, with no in-app purchases.
Do Underwater Stopwatch or World Clock have ads?
Neither Underwater Stopwatch nor World Clock shows ads.
Which is updated more often, Underwater Stopwatch or World Clock?
Underwater Stopwatch ships an update every 3 days, and World Clock every 6 weeks. Most recently, Underwater Stopwatch was updated on October 25, 2026 and World Clock on October 7, 2026.

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