Comparison

Intervals Pro vs One Day Stronger

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

One Day Stronger

Features
Read full description

One Day Stronger is a private companion for gambling recovery, built for the moment the urge hits, and for every day after. No accounts. No sign-up. No data leaves your phone. Everything is free. WHEN THE URGE HITS Tap "I want to gamble" and the app walks you through the moment: rate the urge, name the trigger, and see the two paths in front of you, what tonight costs if you gamble, and what tomorrow looks like if you don't, in your own numbers. A 10-minute pause timer, guided breathing, your own relapse prevention plan, and one-tap calls to your trusted person or a local helpline are all right there. WATCH YOUR LIFE COME BACK • A live counter of your days, hours, and minutes free • Money reclaimed from gambling, in your currency • Milestones from your first 24 hours to a year and beyond • A 90-day calendar of your journey UNDERSTAND YOUR PATTERNS • Journal urges, moods, and victories in seconds • A private recovery coach spots your risky days and hours, computed on your phone, never in a cloud • Weekly reports show your resistance rate and what's working TOOLS THAT DO THE HEAVY LIFTING • CBT workbook with five evidence-based exercises • "Understanding Gambling" - how the industry is designed to keep you playing • Debt tracker and Freedom Fund savings goals • Why I Quit Vault: photos, letters, and messages to your future self • Guided breathing: Box, 4-7-8, and calm techniques PRIVATE BY DESIGN Your recovery is nobody's business but yours. One Day Stronger stores everything on your device, uses no analytics or tracking, and never transmits your data anywhere. Delete the app and the data is gone, we never had it. FREE, COMPLETELY Every feature is free. Recovery support shouldn't be a subscription. One Day Stronger is a support tool, not a substitute for professional treatment. If you're in crisis, please contact a local helpline. The app lists them for Ireland, the UK, the US, Canada, Australia, and New Zealand. One more day. That's all it takes to be one day stronger.

Screenshots

Intervals Pro4 screens
One Day Stronger4 screens

Verdict

The call

The clearest difference is in-app purchases: One Day Stronger at none against Intervals Pro's 8. Intervals Pro's advantage is device support (3 vs 1). On price, update cadence, ads and iOS requirement 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. One Day Stronger asks for nothing beyond the download.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly weekly. The most recent releases landed on October 29, 2026 and October 24, 2026 respectively.

Scorecard2 real differences · 8 level
Intervals Pro versus One Day Stronger: the parameters behind the verdict, then further details
ParameterIntervals ProOne Day Stronger
PriceFreeFree
Rating4.8 (14K ratings) — better—
Positive reviews84.3% of reviews—
Number of ratings14K — better—
Update frequencyWeeklyWeekly
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, Apple Watch — betteriPhone
Requires iOS17.516.4 — better
Further details — not scored
Size66 MB31 MB
Age rating4+12+
DeveloperIntervals, LLCDANIEL MCMORROW

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

One Day Stronger

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
None

One Day Stronger

No in-app purchases

Questions

Is Intervals Pro free?
Intervals Pro is free to download, with in-app purchases available.
Is One Day Stronger free?
One Day Stronger is free to download, with no in-app purchases.
Do Intervals Pro or One Day Stronger have ads?
Neither Intervals Pro nor One Day Stronger shows ads.
Which is updated more often, Intervals Pro or One Day Stronger?
Intervals Pro ships an update weekly, and One Day Stronger weekly. Most recently, Intervals Pro was updated on October 29, 2026 and One Day Stronger on October 24, 2026.

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