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.
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.
- 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
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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 app provides a customizable interval timer for various workout types, including HIIT and Tabata. It features a minimalist design, audio guidance, rep counting, and workout history tracking. You can use your favorite music apps while training.
- Customizable timers and presets
- Audio guidance and beep sounds
- Rep counting functionality
- Workout history and calendar view
- Minimalist and glanceable design
- Music app integration
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Core is a professional interval timer for your daily workouts! - Workout with music: just use your favorite music apps while training. - Count Reps: can be used as a counter to count your workout reps. - Minimalist design: elegant interface and glanceable from afar. - Customizable timers: simple to create your own timers and save presets. - Audio Guide: beep sounds to use in noisy environments and voice guidance. - Workout history: keep track of your workout with stats and calendar view. - Suitable for all kinds of interval training: HIIT, Tabata, boxing, yoga, calisthenics, CrossFit, cardio exercises, circuit training and etc. This app includes optional auto-renewable subscriptions: Monthly ($1.99), Yearly ($7.99). Your subscription will be charged to your iTunes account at confirmation of purchase and will automatically renew (at the duration selected) unless auto-renew is turned off at least 24 hours before the end of the current period. Current subscription may not be canceled during the active subscription period; however, you can manage your subscription and/or turn off auto-renewal by visiting your iTunes Account Settings after purchase. Privacy policy: https://xydigital.studio/Privacy-Policy-4e08709f9d9144558415c7776536786d Terms of use: https://xydigital.studio/Terms-of-Use-5d480081e6624643a7ac87cc87caf9f9 If you have any ideas to improve the App, please contact us via coretimerapp@gmail.com. Your feedback is highly valued!
Screenshots
Verdict
The clearest difference is ads: Interval Timer at none against HIIT Interval Timer | Cero's shown. Interval Timer also leads on review sentiment (100% vs 75%) and rating (5.0 vs 4.7). HIIT Interval Timer | Cero's advantage is update cadence (every 3 days vs every 3 weeks) and ratings volume (435 vs 3). On price, in-app purchases, monetization model and device support 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. HIIT Interval Timer | Cero sells 1 one-off in-app purchase and Interval Timer sells 3 in-app purchases, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.
Interval Timer holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: HIIT Interval Timer | Cero has 435 ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 75% of HIIT Interval Timer | Cero's written reviews are positive against 100% of Interval Timer's.
HIIT Interval Timer | Cero ships an update every 3 days, Interval Timer every 3 weeks. The most recent releases landed on September 29, 2026 and September 23, 2026 respectively.
| Parameter | HIIT Interval Timer | Cero | Interval Timer |
|---|---|---|
| Price | Free | Free |
| Rating | 4.7 (435 ratings) | 5.0 (3 ratings) — better |
| Positive reviews | 74.6% of reviews | 100.0% of reviews — better |
| Number of ratings | 435 — better | 3 |
| Update frequency | Every 3 days — better | Every 3 weeks |
| Ads | Yes | No — better |
| In-app purchases | Yes | Yes |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Devices | iPhone, iPad, Apple Watch — better | iPhone, iPod |
| Requires iOS | 16.0 | 9.0 — better |
| Further details — not scored | ||
| Size | 42 MB | 91 MB |
| Age rating | 4+ | 4+ |
| Developer | Flawless Studio LLC | Yating Lu |
Customer experience
HIIT Interval Timer | Cero
Interval Timer
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
HIIT Interval Timer | Cero
- Cero Pro$3.99
Interval Timer
- Monthly$1.991 Month
- Yearly$7.991 Year
- Lifetime$9.99
Questions
Is HIIT Interval Timer | Cero free?
Is Interval Timer free?
Which has better reviews, HIIT Interval Timer | Cero or Interval Timer?
Do HIIT Interval Timer | Cero or Interval Timer have ads?
Which is updated more often, HIIT Interval Timer | Cero or Interval Timer?
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