Interval Timer for HIIT | Cero vs Interval Timer
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Interval Timer for HIIT | Cero
Create custom interval workouts for HIIT, Tabata, and circuit training. Features adaptive heart rate training, Siri integration, and Apple Watch support. Track progress and share your custom routines.
- Customizable interval programming
- Adaptive heart rate training
- Siri and Shortcuts integration
- Apple Watch app
- Workout history and sharing
- Live Activities and Dynamic Island support
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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/
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.
- 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)
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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
Verdict
The clearest difference is update cadence: Interval Timer for HIIT | Cero at every 3 days against Interval Timer's every 2 months. Interval Timer's advantage is review sentiment (84% vs 75%) and iOS requirement (13.0 vs 18.0). On price, rating, ratings volume and ads 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
Both are free to download. Interval Timer for HIIT | Cero sells 2 in-app purchases, starting at $2.99 per month and Interval Timer sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.
Interval Timer holds the better App Store score, 4.9 against 4.7. Both are backed by a comparable volume of ratings — 438 and 250 respectively. Written reviews point the same way: 75% of Interval Timer for HIIT | Cero's written reviews are positive against 84% of Interval Timer's.
Interval Timer for HIIT | Cero ships an update every 3 days, Interval Timer every 2 months. The most recent releases landed on November 6, 2026 and November 7, 2026 respectively.
| Parameter | Interval Timer for HIIT | Cero | Interval Timer |
|---|---|---|
| Price | Free | Free |
| Rating | 4.7 (438 ratings) | 4.9 (250 ratings) — better |
| Positive reviews | 74.6% of reviews | 84.1% of reviews — better |
| Number of ratings | 438 — better | 250 |
| Update frequency | Every 3 days — better | Every 2 months |
| Ads | Yes | Yes |
| In-app purchases | Yes | Yes |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Devices | iPhone, iPad, Apple Watch | iPhone, iPad, iPod, Apple Watch — better |
| Requires iOS | 18.0 | 13.0 — better |
| Further details — not scored | ||
| Size | 50 MB | 12 MB |
| Age rating | 4+ | 4+ |
| Developer | Flawless Studio LLC | Yosyp Hameliak |
Customer experience
Interval Timer for HIIT | Cero
Interval Timer
User reviews
Interval Timer for HIIT | Cero
From 438 App Store ratingsWhat we love
- 👍 Simple and straightforward
- 👍 Very practical and customizable
- 👍 Great for HIIT and Tabata
- 👍 Clear design and easy to use
- 👍 Good value, no subscription
Room to improve
- 🔋 Drains battery
- 🎶 Music playback interrupted
- ⚠️ Ads interrupt timers
- 🔊 Weak or non-functional sound/haptics
- 🔄 Forced updates
Interval Timer
From 250 App Store ratingsWhat we love
- 👍 Simple and intuitive interface
- 🚀 Efficient for workouts
- 💰 One-time purchase option
- ✨ Clean and uncluttered design
- 💪 Great for various training types
Room to improve
- 🔇 Lack of customizable sounds
- 🚫 Ads can be intrusive
- ⚠️ App pauses when phone is locked
- 🗣️ Voice can be monotonous
- 🔄 Inconsistent sound notifications
Bugs and requests
Interval Timer for HIIT | 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
Reported bugs
9 issues- App pauses when phone is locked
- Sound notifications are inconsistent
- App doesn't run in background
- Watch app not opening or syncing
- In-app purchase issues
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- Timer not counting when phone is locked
- Voice/sound stops during exercises
- Incorrect number of sets displayed
- App crashes or freezes
Requested features
12 requests- Option for different/upbeat voice
- Ability to reorder saved timers
- Larger font size option
- Vibrate option
- Naming individual sets/exercises
Show 7 moreShow fewer
- Audio configuration for set completion
- Syncing workouts with health apps
- Option to keep app running when phone is locked
- Customizable warm-up per saved timer
- Option for giant font size for numbers
- Ability to move saved timers
- More sound options
In-app purchases
Interval Timer for HIIT | Cero
- Cero Pro Monthly7 Days trial$2.991 Month
- Cero Pro$14.99
Interval Timer
- Remove Ads$4.99
Questions
Is Interval Timer for HIIT | Cero free?
Is Interval Timer free?
Which has better reviews, Interval Timer for HIIT | Cero or Interval Timer?
Do Interval Timer for HIIT | Cero or Interval Timer have ads?
Which is updated more often, Interval Timer for HIIT | Cero or Interval Timer?
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