Comparison

btwb vs Interval Flow

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

Head to head
About

btwb

Log your workouts, discover new ones, and connect with your fitness community. Track progress, analyze performance, and manage nutrition with a comprehensive fitness tracking tool.

Highlights
  • Daily workout programming
  • Discover millions of WODs
  • Track workout results
  • Macro and nutrition tracking
  • Community and social features
  • Performance analysis and badges
  • Gym virtual programming
Features
Read full description

btwb, the world's premier workout tracker, brings fitness communities together, in person & remotely. We are the world's largest workout Log with 100+ million results and counting. WORKOUTS - Get daily programming at your fingertips with btwb's Varied Not Random workouts. 4 versions available daily: Performance, Fitness, Dumbbell Only, and No Equipment. - Post results for every workout and/or create your own. - Discover the perfect workout among 12+ Million Unique WODs. - Perfectly capture and share your workout experience with attached images and location tagging. - See how you stack up against the world with World-Wide Leaderboards. GYMS - Keep your community connected by taking your gym virtual. Deliver custom programming to groups and individuals, include personalized movement demos and WOD briefs, view member activity and results via gym feeds and leaderboards, and encourage members with emojis & comments through private Squads. MACROS - Track your Macros. Get the best features of other macro tracking apps combined with our best-in-class workout tracking. With over 700k grocery items, 160k restaurant items, and 13k common foods, find exactly the food you’re looking for by searching our library or by scanning the barcode of your favorite packaged item! You can even create your own custom entries! Set your own macronutrient targets, or have coaches set them for you. - Set your own macronutrient targets, or have coaches set them for you. SOCIAL - Create private Squads and build Follow lists to keep up with your friends' results. - Use direct messaging to converse about fitness with individuals and groups. ANALYSIS - Earn badges for various workouts, gymnastics maxes, 1RM lifts, and running & rowing intervals. - Discover potential major and minor strength, mobility, and technique issues in specific categories with Imbalances. - How fit are you? (1-100) Work to unlock your Fitness Level. Track body fat, benchmarks and more!

About

Interval Flow

This app revolutionizes fitness routines with deep customization and advanced tracking for various activities like HIIT, Yoga, and CrossFit. It allows users to create, share, and follow personalized workouts with features like color-coded intervals, real-time progress tracking, and voice assistance.

Highlights
  • Color-coded intervals
  • Customizable circuits
  • Real-time progress tracking
  • Voice assist and search
  • Exercise library
  • Workout sharing
Features
Read full description

Interval Flow: Experience a Workout Revolution Interval Flow is your ultimate fitness companion, designed to transform your workout experience with deep customization and advanced tracking. This versatile app is perfect for a wide range of activities including HIIT, TABATA, CrossFit, Yoga, Pilates, Meditation, and more. With Interval Flow, you can stay focused on your fitness goals while the app handles the details. Key Features: - Color-Coded Intervals: Customize your workout visually with color-coded intervals. Set distinct colors for warm-ups, high-intensity bursts, rest periods, and more, to easily navigate through your routine. - Exercise Library: Build your workouts with ease! Add new exercises or select from the existing ones to tailor your workout to your specific needs. - Real-Time Progress Tracking: Keep a live tab on your workout progress. The dynamic interval list updates in real-time, ensuring you know exactly where you are in your routine. - Customizable Circuits: Create the perfect workout sequence by arranging various exercises into repeatable circuits tailored to your fitness level and goals. - Personalized Interval Warnings: Get timely alerts before an interval ends. Customize the warning sounds to suit your style, ensuring smooth transitions without missing a beat. - Interactive Workflow: Enjoy crafting your workouts with a user-friendly interface that’s as intuitive as it is functional. Setting up your ideal workout regime is now as engaging as the workout itself. - Voice Assist: Let our advanced voice assist guide you through your exercises, announcing what’s next so you can remain focused on your form and intensity. - Voice Search: Quickly find your favorite workouts using voice commands, making your preparation seamless and hands-free. - AirShare: Share your custom workouts with friends or clients effortlessly using AirDrop, enhancing connectivity and interaction. Why Choose Interval Flow? With Interval Flow, you don't just exercise, you experience a revolution in workout efficiency and enjoyment. The app’s intuitive interface and comprehensive customization options make it the optimal companion for anyone serious about fitness. Whether you're powering through a high-intensity session or seeking tranquility in yoga, Interval Flow adapts to your pace and preference. Unlock your potential with Interval Flow – where your workout meets innovation. Interval Flow Subscription: The app includes a 1 month long auto-renewable subscription with a 3-day free trial, which will unlock premium features, like unlimited workouts, timer program editing and autoplay and costs $4.99/ month. It will be charged to your credit card through your iTunes account and will automatically renew unless you canceled at least 24 hours before the end of the current period. Any unused portion of a free trial period will be forfeited when you purchase the subscription. Though your subscription for the current month cannot be canceled, you can turn auto-renewal off in your account settings after purchase. See the instructions here: https://support.apple.com/en-us/HT202039 You can read the terms of use and privacy policy here: https://kapi90.github.io/hiit_timer_privacy_policy.html End User License Agreement (EULA) of the App Store applies: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

btwb4 screens
Interval Flow4 screens

Verdict

The call

The clearest difference is in-app purchases: btwb at none against Interval Flow's 10. btwb also leads on ratings volume (1.5K vs 168) and iOS requirement (15.6 vs 18.6). On price, rating, review sentiment and update cadence 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 Flow sells 10 in-app purchases, starting at $4.99 per 3 months. btwb asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.6 for btwb against 4.7 for Interval Flow. That said, the two scores are not equally well evidenced: btwb has 1.5K ratings behind it against 168, so its average is the more settled of the two. Written reviews are what separate them: 53% of btwb's written reviews are positive against 48% of Interval Flow's.

UpkeepUpdate frequency

btwb ships an update weekly, Interval Flow fortnightly. The most recent releases landed on September 22, 2026 and September 5, 2026 respectively.

Scorecard4 real differences · 6 level
btwb versus Interval Flow: the parameters behind the verdict, then further details
ParameterbtwbInterval Flow
PriceFreeFree
Rating4.6 (1.5K ratings)4.7 (168 ratings) — better
Positive reviews53.2% of reviews — better48.1% of reviews
Number of ratings1.5K — better168
Update frequencyWeekly — betterFortnightly
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree with in-app purchases — betterSubscription
DevicesiPhone, iPod, Apple Watch — betteriPhone, iPad
Requires iOS15.6 — better18.6
Further details — not scored
Size265 MB20 MB
Age rating4+4+
DeveloperBTWB, LLCBence Kaposzta

Customer experience

btwb

All ratings1,528 ratings
Positive89.5%
Neutral2.7%
Negative7.8%
Written reviews203 reviews
Positive53.2%
Neutral9.4%
Negative37.4%

Interval Flow

All ratings168 ratings
Positive93.5%
Neutral2.4%
Negative4.2%
Written reviews27 reviews
Positive48.1%
Neutral18.5%
Negative33.3%

Bugs and requests

btwb

Reported bugs

5 issues
  • Subscription cancellation and billing problems
  • Frequent crashes and white screens
  • Inability to log certain workout types
  • Barcode scanner and movement tracking issues
  • Problems with data syncing and history display

Requested features

5 requests
  • Add dark mode or black background option
  • Integrate with Apple Health and other fitness apps
  • Improve custom workout creation and logging
  • Provide better social/community features
  • Fix issues with loading and saving workout data

Interval Flow

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

btwb

No in-app purchases

10 purchases

Interval Flow

Subscriptions8
  • 3 Month$4.993 Months
  • 1 Month$9.991 Month
  • 1 Month, 3 day trial3 Days trial$9.991 Month
Show 5 more
  • Annual7 Days trial$14.991 Year
  • 1 Year discounted$25.951 Year
  • 1 Year, 3 day trial3 Days trial$39.991 Year
  • 1 Year$39.991 Year
  • 1 Year Intro month1 Month trial$39.991 Year
One-time2
  • Free Lifetime subscriptionFree
  • Lifetime$24.99

Questions

Is btwb free?
btwb is free to download, with no in-app purchases.
Is Interval Flow free?
Interval Flow is free to download, with in-app purchases available.
Which has better reviews, btwb or Interval Flow?
Interval Flow is rated higher. btwb averages 4.6 out of 5 from 1.5K ratings, while Interval Flow averages 4.7 from 168 ratings.
Do btwb or Interval Flow have ads?
Neither btwb nor Interval Flow shows ads.
Which is updated more often, btwb or Interval Flow?
btwb ships an update weekly, and Interval Flow fortnightly. Most recently, btwb was updated on September 22, 2026 and Interval Flow on September 5, 2026.

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