Comparison

HIIT Interval Timer | Cero vs Interval Timer

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

Head to head
About

HIIT Interval Timer | Cero

This interval timer app enhances various workouts like HIIT, Tabata, and yoga with intuitive design and customizable timer modes. Create and save custom intervals, track calorie expenditure, and sync settings across devices, including Apple Watch.

Highlights
  • Customizable interval timers
  • Simple and advanced timer modes
  • Create and save multiple workout settings
  • Apple Watch compatibility with heart monitor
  • Automatic calorie tracking to Apple Health
  • Cross-device sync
Features
Read full description

Build an interval workout around the way you train. Cero is a flexible interval timer for HIIT, Tabata, circuit training, WODs and HYROX preparation. Set up a quick work/rest timer or program each interval in detail. Distinct colors, large controls and reliable cues keep you focused on the session instead of the clock. BUILD YOUR SESSION • Set work, recovery, sets, warm-up and cool-down. • Create advanced workouts with custom intervals, colors, icons and intensity levels. • Save, duplicate and reorder timers. • Share timers by file or QR code. • Review completed sessions in workout history. STAY IN THE WORKOUT • Follow compatible sessions with Live Activities and Dynamic Island. • Start saved or recent timers from Home Screen widgets. • Use Siri and Shortcuts to start, pause, resume and stop a timer. • Put Gym Display on a larger screen or mirrored TV. • Choose a default song or assign music to individual intervals. • Customize sounds, voice cues, vibrations and background alerts. TRAIN BY HEART RATE Adaptive HR can extend recovery until you reach your target heart rate, then guide hard efforts with low and high alerts. Pair a Bluetooth heart-rate monitor with iPhone or train with heart-rate data from Apple Watch. COUNTDOWN AND STOPWATCH The built-in countdown and lap stopwatch cover warm-ups, station changes, rest periods and race-day practice. Stopwatch sessions continue after you close and reopen the app. ON APPLE WATCH Run saved workouts from your wrist, follow heart rate and use the standalone countdown and stopwatch. Cero can save completed workouts and estimated calories to Apple Health. Automatic iCloud backups help protect saved timers and custom intervals. Useful for HIIT, Tabata, circuits, EMOM-style workouts, boxing rounds, strength and conditioning, indoor cycling, running intervals and hybrid race preparation. Feedback and suggestions: hi@flawless.studio Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Interval Timer

This interval timer is designed for HIIT and interval training. Easily set work and rest periods, sets, and rounds to guide your workouts. It supports background operation and music playback, with an Apple Watch companion app for heart rate monitoring.

Highlights
  • Customizable work and rest periods
  • Set number of sets and rounds
  • Background operation support
  • Music playback compatibility
  • Apple Watch integration
  • Heart rate monitoring (Apple Watch)
Features
Read full description

This app is handy interval timer that helps you keep track of your work and rest periods during your HIIT interval training and workouts. The application is very easy to use, enter the Work, Rest, Sets, Rounds and start workout. You can listen to music during workouts or use the timer in the background. There is also app on the Apple Watch that will allow you to monitor your heart rate during workouts. Apple Watch app features: - iCloud sync with iPhone - integration with the Health app - monitoring heart rate during workouts

Screenshots

HIIT Interval Timer | Cero4 screens
Interval Timer4 screens

Verdict

The call

The clearest difference is update cadence: HIIT Interval Timer | Cero at every 3 days against Interval Timer's every 2 months. Interval Timer's advantage is rating (4.9 vs 4.7) and review sentiment (84% vs 75%). On price, ratings volume, ads and in-app purchases 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. HIIT Interval Timer | Cero sells 1 one-off in-app purchase and Interval Timer sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Interval Timer holds the better App Store score, 4.9 against 4.7. Both are backed by a comparable volume of ratings — 435 and 246 respectively. Written reviews point the same way: 75% of HIIT Interval Timer | Cero's written reviews are positive against 84% of Interval Timer's.

UpkeepUpdate frequency

HIIT Interval Timer | Cero ships an update every 3 days, Interval Timer every 2 months. The most recent releases landed on September 29, 2026 and September 28, 2026 respectively.

Scorecard4 real differences · 6 level
HIIT Interval Timer | Cero versus Interval Timer: the parameters behind the verdict, then further details
ParameterHIIT Interval Timer | CeroInterval Timer
PriceFreeFree
Rating4.7 (435 ratings)4.9 (246 ratings) — better
Positive reviews74.6% of reviews83.5% of reviews — better
Number of ratings435 — better246
Update frequencyEvery 3 days — betterEvery 2 months
AdsYesYes
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, Apple WatchiPhone, iPad, iPod, Apple Watch — better
Requires iOS16.013.0 — better
Further details — not scored
Size42 MB12 MB
Age rating4+4+
DeveloperFlawless Studio LLCYosyp Hameliak

Customer experience

HIIT Interval Timer | Cero

All ratings435 ratings
Positive92.9%
Neutral3.9%
Negative3.2%
Written reviews59 reviews
Positive74.6%
Neutral10.2%
Negative15.3%

Interval Timer

All ratings246 ratings
Positive97.6%
Neutral0.8%
Negative1.6%
Written reviews85 reviews
Positive83.5%
Neutral4.7%
Negative11.8%

Bugs and requests

HIIT Interval Timer | Cero

Reported bugs

4 issues
  • App runs in background draining battery
  • Rotation broke after update
  • Apple workout app overrides Cero app on Apple Watch
  • Interval signals too weak or not working

Requested features

5 requests
  • Ability to group timers
  • Option to add warm-up and cool-down features
  • Ability to type numbers for time adjustment
  • Timer sounds through headphones or interrupting music
  • Ability to change exercise names

Interval Timer

Not enough reviews yet to summarise bugs or requests.

In-app purchases

1 purchases

HIIT Interval Timer | Cero

One-time1
  • Cero Pro$3.99
1 purchases

Interval Timer

One-time1
  • Remove Ads$4.99

Questions

Is HIIT Interval Timer | Cero free?
HIIT Interval Timer | Cero is free to download, with in-app purchases available.
Is Interval Timer free?
Interval Timer is free to download, with in-app purchases available.
Which has better reviews, HIIT Interval Timer | Cero or Interval Timer?
Interval Timer is rated higher. HIIT Interval Timer | Cero averages 4.7 out of 5 from 435 ratings, while Interval Timer averages 4.9 from 246 ratings.
Do HIIT Interval Timer | Cero or Interval Timer have ads?
Both HIIT Interval Timer | Cero and Interval Timer show ads.
Which is updated more often, HIIT Interval Timer | Cero or Interval Timer?
HIIT Interval Timer | Cero ships an update every 3 days, and Interval Timer every 2 months. Most recently, HIIT Interval Timer | Cero was updated on September 29, 2026 and Interval Timer on September 28, 2026.

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