Comparison

Interval Timer vs AER

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

Head to head
About

Interval Timer

This app provides a customizable interval timer for various training routines, including HIIT and Tabata. Easily set up custom workouts, track your progress, and stay motivated with visual cues and audio notifications. It's suitable for a wide range of activities from fitness to productivity.

Highlights
  • Customizable workout setup
  • Progress tracking with calendar
  • Saveable custom presets
  • Color-coded notifications
  • Listen to music/audiobooks
  • Large, full-screen display
  • Widget for easy access
Features
Read full description

Interval Timer: Tabata and HIIT is a customizable timer for sports. Use it for High-intensity interval training and workout. It's a free sports interval timer app that makes it easy to create your custom training routine. Use it as your timer for training or exercise. This sports timer is great for crossfit, fitness and running. The sports timer will also be useful for various activities such as crossfit, jogging, boxing,circuit training,breathing exercises and yoga. You can use this circuit timer as a productivity timer to focus on your work tasks. Key features: Setup workout Tracking your progress Customizable presets Notifications & colors Motivation Listening music or books Huge digits Widget SETUP WORKOUT Set up, edit and save your own workouts with the customizable feature. Add as many intervals as you like. You can add a 10 second rest period and a 20 second work period, as well as a 5 second interval between exercises. TRACKING PROGRESS Track your workouts with a Calendar. Plan and track events, and get notified when you have a training scheduled. With this feature, you will not miss a single workout and will keep track of your progress. CUSTOMIZABLE PRESETS Save your workouts in the presets section. It's also possible to create your own custom intervals. You can add an unlimited number of presets. NOTIFICATIONS & COLORS Each training phase is easy to distinguish by a different color and is initiated by an individually adjustable signal (sound, vibration, voice) MOTIVATION Each completed exercise motivates you to achieve higher goals. Enjoy your training and achieve your fitness goals with the interval timer. LISTENING MUSIC Listen to motivational audiobooks or your favorite music and get inspired and energized. Full screen color coded display is easy to read from a distance. Widget helps you train without being distracted by the constant unlocking of your phone. Interval Timer: Tabata and HIIT is an easy to use sports workout timer for your daily fitness training at home, at the gym or everywhere else.

About

AER

This app guides you through breathing exercises for relaxation, focus, and sleep. Follow animated visuals and optional audio cues to achieve calm and clarity.

Highlights
  • Guided breathing sessions
  • Relaxation techniques
  • Focus enhancement
  • Sleep aid
  • Animated visual guide
  • Ambient sound options
Features
Read full description

AER helps you slow down and breathe with guided sessions for relaxation, focus, balance, and sleep. Choose a breathing pattern, follow the animated circle, and use optional ambient sound and coach chat to support calm, clarity, and recovery.

Screenshots

Interval Timer4 screens
AER4 screens

Verdict

The call

The clearest difference is in-app purchases: AER at none against Interval Timer's 10. AER also leads on ads (none vs shown) and update cadence (every 5 days vs monthly). Interval Timer's advantage is ratings volume (391 vs 1). On price, rating, review sentiment 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 sells 10 in-app purchases, starting at $2.09 per month. AER asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.9 for Interval Timer against 5.0 for AER. That said, the two scores are not equally well evidenced: Interval Timer has 391 ratings behind it against 1, so its average is the more settled of the two. Written reviews are what separate them: 97% of Interval Timer's written reviews are positive against 100% of AER's.

UpkeepUpdate frequency

Interval Timer ships an update monthly, AER every 5 days. The most recent releases landed on November 3, 2026 and October 31, 2026 respectively.

Scorecard5 real differences · 5 level
Interval Timer versus AER: the parameters behind the verdict, then further details
ParameterInterval TimerAER
PriceFreeFree
Rating4.9 (391 ratings)5.0 (1 ratings) — better
Positive reviews96.6% of reviews100.0% of reviews — better
Number of ratings391 — better1
Update frequencyMonthlyEvery 5 days — better
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPad, iPod, Apple Watch — betteriPhone, iPad, iPod
Requires iOS15.015.0
Further details — not scored
Size112 MB17 MB
Age rating4+4+
DeveloperSimpleInnovation LLCViktor Danyshchuk

Customer experience

Interval Timer

All ratings388 ratings
Positive99.5%
Neutral0.3%
Negative0.3%
Written reviews321 reviews
Positive96.6%
Neutral0.9%
Negative2.5%

AER

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

Interval Timer

Reported bugs

2 issues
  • Occasional app crashes
  • Compatibility issues with older devices

Requested features

3 requests
  • More pre-designed workout routines
  • Ability to name and customize exercises
  • Option to adjust countdown time between intervals

AER

Not enough reviews yet to summarise bugs or requests.

In-app purchases

10 purchases

Interval Timer

Subscriptions7
  • Timer PRO for 1 month: 30% OFF7 Days trial$2.091 Month
  • Timer PRO for 1 month: 25% OFF7 Days trial$2.291 Month
  • Interval Timer PRO for 1 month$2.991 Month
Show 4 more
  • Interval Timer PRO for 1 month7 Days trial$2.991 Month
  • Interval Timer PRO - 30% OFF7 Days trial$15.001 Year
  • Interval Timer PRO for 1 year$21.991 Year
  • Tabata Timer PRO for 1 year7 Days trial$21.991 Year
One-time3
  • Interval Timer - no Ads$2.99
  • HIIT Timer PRO Forever 30% OFF$27.99
  • Exercise Timer PRO Forever$39.99
None

AER

No in-app purchases

Questions

Is Interval Timer free?
Interval Timer is free to download, with in-app purchases available.
Is AER free?
AER is free to download, with no in-app purchases.
Which has better reviews, Interval Timer or AER?
AER is rated higher. Interval Timer averages 4.9 out of 5 from 391 ratings, while AER averages 5.0 from 1 ratings.
Do Interval Timer or AER have ads?
Interval Timer shows ads; AER does not.
Which is updated more often, Interval Timer or AER?
Interval Timer ships an update monthly, and AER every 5 days. Most recently, Interval Timer was updated on November 3, 2026 and AER on October 31, 2026.

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