Comparison

Interval Timer for HIIT | Cero vs Interval Timer Pro+

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

Head to head
About

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.

Highlights
  • Customizable interval programming
  • Adaptive heart rate training
  • Siri and Shortcuts integration
  • Apple Watch app
  • Workout history and sharing
  • Live Activities and Dynamic Island support
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 Pro+

This app guides you through interval-based workouts, including Tabata and HIIT, with clear instructions for exercises, rest periods, and rounds. It offers workout history and integrates with Apple Watch for calorie and heart rate tracking.

Highlights
  • Simple workout setup
  • Advanced workout creation
  • Exercise naming and warmup
  • Workout history tracking
  • Apple Watch integration
  • Health app integration
Features
Read full description

Interval Timer Pro+ is a perfect interval based workouts app to use at your home, outside or gym. Tabata workouts never been easier! This app guides you though exercises, resting and rounds at ease. Time left for current exercise, resting time and what's coming next. Key features: * Simple workout that is ease to set up. * Advanced workouts creation with warmup and exercise naming. * History of your exercises. * If you have an apple watch app will show active calories burned and your heart rate. This app integrates with the Health app. For users that have purchased additional features we show active and total calories collected by apple watch. We also show heart rate when running a workout. Data from Health app is used to display this data.

Screenshots

Interval Timer for HIIT | Cero4 screens
Interval Timer Pro+4 screens

Verdict

The call

The clearest difference is review sentiment: Interval Timer for HIIT | Cero at 75% against Interval Timer Pro+'s 0%. Interval Timer for HIIT | Cero also leads on rating (4.7 vs 1.0) and update cadence (every 3 days vs every 3 months). Interval Timer Pro+'s advantage is ads (none vs shown) and iOS requirement (15.0 vs 18.0). 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Interval Timer for HIIT | Cero sells 2 in-app purchases, starting at $2.99 per month and Interval Timer Pro+ 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 for HIIT | Cero holds the better App Store score, 4.7 against 1.0. That said, the two scores are not equally well evidenced: Interval Timer for HIIT | Cero has 438 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 75% of Interval Timer for HIIT | Cero's written reviews are positive against 0% of Interval Timer Pro+'s.

UpkeepUpdate frequency

Interval Timer for HIIT | Cero ships an update every 3 days, Interval Timer Pro+ every 3 months. The most recent releases landed on November 6, 2026 and November 3, 2026 respectively.

Scorecard6 real differences · 4 level
Interval Timer for HIIT | Cero versus Interval Timer Pro+: the parameters behind the verdict, then further details
ParameterInterval Timer for HIIT | CeroInterval Timer Pro+
PriceFreeFree
Rating4.7 (438 ratings) — better1.0 (1 ratings)
Positive reviews74.6% of reviews — better0.0% of reviews
Number of ratings438 — better1
Update frequencyEvery 3 days — betterEvery 3 months
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, Apple WatchiPhone, iPad, iPod, Apple Watch — better
Requires iOS18.015.0 — better
Further details — not scored
Size50 MB28 MB
Age rating4+4+
DeveloperFlawless Studio LLCKarolis Raiselis

Customer experience

Interval Timer for HIIT | Cero

All ratings438 ratings
Positive92.9%
Neutral3.9%
Negative3.2%
Written reviews59 reviews
Positive74.6%
Neutral10.2%
Negative15.3%

Interval Timer Pro+

All ratings1 ratings
Positive0.0%
Neutral0.0%
Negative100.0%
Written reviews1 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

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 Pro+

Not enough reviews yet to summarise bugs or requests.

In-app purchases

2 purchases

Interval Timer for HIIT | Cero

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

Interval Timer Pro+

One-time1
  • Upgrade to Premium$1.99

Questions

Is Interval Timer for HIIT | Cero free?
Interval Timer for HIIT | Cero is free to download, with in-app purchases available.
Is Interval Timer Pro+ free?
Interval Timer Pro+ is free to download, with in-app purchases available.
Which has better reviews, Interval Timer for HIIT | Cero or Interval Timer Pro+?
Interval Timer for HIIT | Cero is rated higher. Interval Timer for HIIT | Cero averages 4.7 out of 5 from 438 ratings, while Interval Timer Pro+ averages 1.0 from 1 ratings.
Do Interval Timer for HIIT | Cero or Interval Timer Pro+ have ads?
Interval Timer for HIIT | Cero shows ads; Interval Timer Pro+ does not.
Which is updated more often, Interval Timer for HIIT | Cero or Interval Timer Pro+?
Interval Timer for HIIT | Cero ships an update every 3 days, and Interval Timer Pro+ every 3 months. Most recently, Interval Timer for HIIT | Cero was updated on November 6, 2026 and Interval Timer Pro+ on November 3, 2026.

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