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 app helps you structure workouts with customizable timers for high-intensity intervals and rest periods. Track your progress, create personalized training plans, or use recommendations to achieve fitness goals. Enhance your sessions with customizable themes, sounds, and voiceovers.

Highlights
  • Customizable interval timers
  • Workout logging
  • Personalized training programs
  • Recommended routines
  • Customizable themes and sounds
  • Multiple voiceover options
Features
Read full description

An easy-to-use timer app useful for gym and home workouts and for separating periods of high activity and rest to stay most productive during your day. Create your own training programs or use our recommendations to suit your goals. Keep a daily workout log and motivate yourself to achieve new goals. Many options for customizing the appearance of the application, such as color themes, sounds and multiple voiceover choises. You will never miss a signal again. With this app you can get in shape, lose weight, keep a clear and focused mind and became more healthfull person. Privacy policy: https://timer.works/privacy.html Terms of Use: https://timer.works/terms.html

Screenshots

HIIT Interval Timer | Cero4 screens
Interval timer3 screens

Verdict

The call

The clearest difference is ads: Interval timer at none against HIIT Interval Timer | Cero's shown. Interval timer also leads on update cadence (daily vs every 3 days) and iOS requirement (14.0 vs 16.0). HIIT Interval Timer | Cero's advantage is ratings volume (435 vs 37). On price, rating, in-app purchases and monetization model 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 2 in-app purchases, starting at $2.99 per month and Interval timer sells 3 in-app purchases, starting at $2.49 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. That said, the two scores are not equally well evidenced: HIIT Interval Timer | Cero has 435 ratings behind it against 37, so its average is the more settled of the two.

UpkeepUpdate frequency

HIIT Interval Timer | Cero ships an update every 3 days, Interval timer daily. The most recent releases landed on October 16, 2026 and October 7, 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)4.8 (37 ratings) — better
Positive reviews74.6% of reviews—
Number of ratings435 — better37
Update frequencyEvery 3 daysDaily — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchasesFreemium
DevicesiPhone, iPad, Apple Watch — betteriPhone, iPod
Requires iOS16.014.0 — better
Further details — not scored
Size42 MB28 MB
Age rating4+4+
DeveloperFlawless Studio LLCDmitriy Beloglazov

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 ratings37 ratings
Positive94.6%
Neutral0.0%
Negative5.4%

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

2 purchases

HIIT Interval Timer | Cero

Subscriptions1
  • Cero Pro Monthly7 Days trial$2.991 Month
One-time1
  • Cero Pro$14.99
3 purchases

Interval timer

Subscriptions3
  • Premium - Week3 Days trial$2.497 Days
  • Premium - Month3 Days trial$5.991 Month
  • Premium - Year$19.491 Year

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 4.8 from 37 ratings.
Do HIIT Interval Timer | Cero or Interval timer have ads?
HIIT Interval Timer | Cero shows ads; Interval timer does not.
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 daily. Most recently, HIIT Interval Timer | Cero was updated on October 16, 2026 and Interval timer on October 7, 2026.

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