Comparison

Intervals Pro vs Interval Timer by STRNTH

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

Head to head
About

Intervals Pro

Create and follow custom interval training routines for various fitness activities. This app offers extensive customization for intervals, alerts, and goals, with seamless integration for Apple Watch and Apple Health.

Highlights
  • Highly customizable intervals (time/distance)
  • Spoken interval names and prompts
  • Standalone Apple Watch workouts
  • Workout history with Apple Health
  • Home screen widgets for quick launch
  • Bluetooth heart rate monitor support
  • Siri Shortcuts integration
Features
Read full description

Custom Interval Training at its best for iPhone, Apple Watch and iPad. Featured by Apple and recommended by fitness instructors, personal trainers, marathon runners, and coaches. Let Intervals Pro guide you through any type of interval workout: HIIT, running, strength training, yoga, stretching, circuit training, boxing, MMA, elliptical, rehabilitation, meditation, 7-minute workouts, and many more. FEATURED BY • Apple - App of the Day in 132 Countries • Apple - Workout with Apple Watch, Quick HIIT Workouts • Women's Health Magazine • COACH Magazine • SixColors.com HIGHLIGHTS • Highly Customizable • Home Screen Widgets to quickly launch timers • Spoken interval names and prompts • Customizable alert sounds • Standalone Apple Watch workouts. Leave your iPhone at home! • Workout History using Apple Health data • View an Apple Watch workout live on your iPhone! • Run in the background with the screen locked • Play music or podcasts using the app of your choice • Bluetooth heart rate monitor support for Apple Watch or iPhone • Fill your Activity Rings • Siri Shortcuts • Share timers with friends • Time and Distance Goals • Running Pace and Heart Rate Targets • Auto pause and resume • Send completed workouts to Strava • Confetti! PERSONALIZE YOUR WORKOUT • Customize the Name, Duration, Alert, and Color for each interval • Customize Alert Sounds and Voice Prompts to guide you through your workout • Set a Countdown Alert and vibrations when the interval is about to end • Optional halfway alert • Set target heart rate ranges for each interval • Set time and distance goals FLEXIBLE INTERVAL DURATIONS • Time based (e.g., 45 seconds) • Distance-based (e.g., 0.5 MI or KM) • Count up intervals keep running until your ready for the next interval • Estimated time or distance. Count down time or distance to zero and then continue the interval, counting up until you're ready to move on. THE BEST APPLE WATCH INTERVAL TIMER • Leave your phone at home with our standalone Apple Watch app • Control your music or podcasts on the "Now Playing" screen • View an Apple Watch workout live on your iPhone • Alert Sounds and Voice Prompts to guide you through your workout • Configurable haptic alert countdown that taps you on the wrist when the interval is ending • Track heart rate, calories, distance, and pace • Route tracking for running, walking, and cycling • Workouts contribute to the Apple Watch Activity Rings WORKOUT HISTORY USING APPLE HEALTH • Intervals Pro has the best Apple Health integration of any interval training app • Track heart rate, calories, distance, and pace • Route tracking for running, walking, and cycling • Detailed stats for every interval • All your data is safely stored in Apple Health GREAT FOR RUNNING AND CYCLING • Interval duration can be set to either a specified time or distance • Display current pace, pace for the interval, or pace for the entire run • Configure heart rate ranges per interval • Analyze each interval of your run in the workout history MULTIPLE VOICES AND LANGUAGES • Select the language and voice to use for all spoken alerts. • Spoken alerts are localized to 10 languages. Chinese (simplified), Danish, Dutch, French, German, Italian, Norwegian, Polish, Spanish, and Swedish. Get Intervals Pro today, and your workouts will never be the same! SUBSCRIPTION INFO Intervals Pro is free to download and has a free timer. To create multiple timers and unlock all the features of the app, you may choose between a monthly or yearly auto-renewing subscription option. Upon confirmation of the purchase, payment will be charged to your credit card through your iTunes account. Subscription renews automatically unless canceled at least 24 hours before the end of the subscription period. Subscriptions can be managed and auto-renewal turned off in Account Settings in the App Store app. Privacy Policy and Terms of Service: https://intervalspro.com/privacy-policy.html

About

Interval Timer by STRNTH

Features
Read full description

Interval Timer by STRNTH is a free interval timer for HIIT, Tabata, EMOM, AMRAP, boxing rounds, running intervals, stretching and more. Build any timer you want with no fixed structure, then run it hands-free and read it from across the room. BUILD ANY TIMER - Add as many steps as you like, each with its own label, duration, colour, sound and voice. - Group steps into repeat blocks so a round loops as many times as you need. - Link separate timers together to chain a warm-up, workout and cool-down into one session. - Start from a template: Couch to 5K, Tabata, HIIT, 7 minute workout, EMOM, AMRAP, boxing rounds, Pomodoro, box breathing and full body stretch. RUN IT HANDS-FREE - A giant readout inside a progress ring, sized to read from across the gym. - Full-screen colour per step so you know your phase at a glance. - Voice reads each step and announces what is next before it arrives. - Sound cues on the last three seconds, plus beep, go, switch, rest, bell, horn, gong and whistle tones. Import your own sounds too. - Optional spoken 3-2-1 countdown, a cadence metronome from 60 to 180 BPM and haptic feedback. - Choose what the screen shows: interval time, total time, interval count, the clock or heart rate. MORE TOOLS - A countdown tab with quick presets for a fast single timer. - A stopwatch with laps that highlight your fastest and slowest split. - Light and dark themes and your own custom step colours. - Share a timer as a link or a file, and import timers others send you. ACROSS YOUR DEVICES - An Apple Watch companion runs your timers on the wrist with colour and haptics. - Pair a Bluetooth heart rate strap to see live BPM, zones and more while you train. - Save finished sessions to Apple Health as workouts. - Back up your timers to your private iCloud. FREE, WITH A ONE-TIME UPGRADE Interval Timer is free and supported by ads. A single 9.99 purchase removes ads for good. No accounts, no subscriptions, no cloud sign-in. Your timers stay on your device. Part of the STRNTH family of training apps.

Screenshots

Intervals Pro4 screens
Interval Timer by STRNTH4 screens

Verdict

The call

The clearest difference is ads: Intervals Pro at none against Interval Timer by STRNTH's shown. Interval Timer by STRNTH's advantage is iOS requirement (15.1 vs 17.5). On price, update cadence, in-app purchases 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. Intervals Pro sells 8 in-app purchases, starting at $2.99 per month and Interval Timer by STRNTH sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Intervals Pro ships an update every 8 days, Interval Timer by STRNTH every 10 days. The most recent releases landed on September 24, 2026 and September 18, 2026 respectively.

Scorecard2 real differences · 8 level
Intervals Pro versus Interval Timer by STRNTH: the parameters behind the verdict, then further details
ParameterIntervals ProInterval Timer by STRNTH
PriceFreeFree
Rating4.8 (14K ratings) — better—
Positive reviews84.4% of reviews—
Number of ratings14K — better—
Update frequencyEvery 8 days — betterEvery 10 days
AdsNo — betterYes
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, Apple WatchiPhone, iPad, iPod, Apple Watch — better
Requires iOS17.515.1 — better
Further details — not scored
Size69 MB55 MB
Age rating4+12+
DeveloperIntervals, LLCNext Big Leap Ltd

Bugs and requests

Intervals Pro

Reported bugs

2 issues
  • Workout data not syncing correctly
  • App crashes or freezes on certain devices

Requested features

3 requests
  • More customization options for interval displays
  • Ability to batch delete or manage workout history
  • Integration with more third-party fitness apps

Interval Timer by STRNTH

Not enough reviews yet to summarise bugs or requests.

In-app purchases

8 purchases

Intervals Pro

Subscriptions2
  • Monthly Membership7 Days trial$2.991 Month
  • Yearly Membership7 Days trial$19.991 Year
One-time6
  • Generous Tip$0.99
  • Awesome Tip$1.99
  • Massive Tip$4.99
Show 3 more
  • Amazing Tip$9.99
  • Intervals Pro (Legacy)$69.99
  • Lifetime Access$69.99
1 purchases

Interval Timer by STRNTH

One-time1
  • Remove ads$9.99

Questions

Is Intervals Pro free?
Intervals Pro is free to download, with in-app purchases available.
Is Interval Timer by STRNTH free?
Interval Timer by STRNTH is free to download, with in-app purchases available.
Do Intervals Pro or Interval Timer by STRNTH have ads?
Interval Timer by STRNTH shows ads; Intervals Pro does not.
Which is updated more often, Intervals Pro or Interval Timer by STRNTH?
Intervals Pro ships an update every 8 days, and Interval Timer by STRNTH every 10 days. Most recently, Intervals Pro was updated on September 24, 2026 and Interval Timer by STRNTH on September 18, 2026.

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