Comparison

HIIT Interval Timer | Cero vs Interval timer · Hiit 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 · Hiit timer

This workout app offers customizable interval and rest times, with audio guidance that continues even when the app is in the background. Track your progress with detailed history and statistics, and easily repeat past workouts. It's designed to enhance your fitness routine without interrupting your music.

Highlights
  • Customizable interval and rest times
  • Audio guidance (voice or beeps)
  • Background audio support
  • Workout history and statistics
  • Repeat previous workouts
  • Non-interference with music
Features
Read full description

Interval Timer is a flexible and convenient workout app with the following notable features: • Customizable Time Settings: You can easily drag and drop to set the time for workout intervals and rest periods according to your preferences. • Easy Start: Simply tap to begin the countdown timer and start your workout session. • Non-Interference with Music: The app does not interrupt the music you are listening to or other apps on your device. • Guidance via Voice or Beeps: You can choose the form of guidance to monitor and adjust your workout pace. • Audio Guidance even when run the app in background: You can exit the app and still receive guidance through audio, allowing you to focus fully on your exercises. • Detailed History and Statistics: Track your workout progress through automatically recorded data and metrics. • Repeat Previous Workouts: Save time by reusing previous setups and exercises from your workout history. • Multi-Functional Timer: Besides being a workout timer, it can also be used for various other timing purposes. These features make Interval Timer an essential and effective workout assistant for anyone dedicated to improving their fitness and health. Download now to experience and enhance your workout performance starting today! Upgrade to Premium: • Interval Timer subscription is billed monthly to the selected plan. Payment will be charged to iTunes Account at confirmation of purchase. Subscription automatically renews unless auto-renew is turned off at least 24-hours before the end of the current period. • Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user's Account Settings after purchase Let us know about any bugs, questions, feature requests or any other suggestions. Thank you For more infos, Please visit: https://apps.unitvn.com/terms https://apps.unitvn.com/policy

Screenshots

HIIT Interval Timer | Cero4 screens
Interval timer · Hiit timer4 screens

Verdict

The call

The clearest difference is ratings volume: HIIT Interval Timer | Cero at 435 against Interval timer · Hiit timer's 16. HIIT Interval Timer | Cero also leads on update cadence (every 3 days vs weekly). Interval timer · Hiit timer's advantage is iOS requirement (14.0 vs 16.0). On price, rating, 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 · Hiit timer sells 3 in-app purchases, starting at $2.99 per 7 days. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.7 for HIIT Interval Timer | Cero against 4.8 for Interval timer · Hiit timer. That said, the two scores are not equally well evidenced: HIIT Interval Timer | Cero has 435 ratings behind it against 16, so its average is the more settled of the two.

UpkeepUpdate frequency

HIIT Interval Timer | Cero ships an update every 3 days, Interval timer · Hiit timer weekly. The most recent releases landed on September 29, 2026 and October 1, 2026 respectively.

Scorecard3 real differences · 7 level
HIIT Interval Timer | Cero versus Interval timer · Hiit timer: the parameters behind the verdict, then further details
ParameterHIIT Interval Timer | CeroInterval timer · Hiit timer
PriceFreeFree
Rating4.7 (435 ratings)4.8 (16 ratings) — better
Positive reviews74.6% of reviews—
Number of ratings435 — better16
Update frequencyEvery 3 days — betterWeekly
AdsYesYes
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, Apple WatchiPhone, iPad, iPod
Requires iOS16.014.0 — better
Further details — not scored
Size42 MB82 MB
Age rating4+4+
DeveloperFlawless Studio LLCUnitVN.,JSC

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 · Hiit timer

All ratings16 ratings
Positive93.8%
Neutral0.0%
Negative6.3%

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 · Hiit 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
3 purchases

Interval timer · Hiit timer

Subscriptions2
  • Premium Weekly3 Days trial$2.997 Days
  • Premium Monthly$4.991 Month
One-time1
  • Lifetime package$19.99

Questions

Is HIIT Interval Timer | Cero free?
HIIT Interval Timer | Cero is free to download, with in-app purchases available.
Is Interval timer · Hiit timer free?
Interval timer · Hiit timer is free to download, with in-app purchases available.
Which has better reviews, HIIT Interval Timer | Cero or Interval timer · Hiit timer?
Interval timer · Hiit timer is rated higher. HIIT Interval Timer | Cero averages 4.7 out of 5 from 435 ratings, while Interval timer · Hiit timer averages 4.8 from 16 ratings.
Do HIIT Interval Timer | Cero or Interval timer · Hiit timer have ads?
Both HIIT Interval Timer | Cero and Interval timer · Hiit timer show ads.
Which is updated more often, HIIT Interval Timer | Cero or Interval timer · Hiit timer?
HIIT Interval Timer | Cero ships an update every 3 days, and Interval timer · Hiit timer weekly. Most recently, HIIT Interval Timer | Cero was updated on September 29, 2026 and Interval timer · Hiit timer on October 1, 2026.

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