Comparison

iFour Core vs Prehab U

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

Head to head
About

iFour Core

This app offers a personalized core workout program designed by physical therapists. It adapts to your individual anatomy and fitness level, providing daily workouts under 10 minutes with video demonstrations. Access nutrition guides and trainer support as a member.

Highlights
  • Personalized core workout program
  • Physical therapy approved exercises
  • Daily workouts under 10 minutes
  • Video demonstrations of exercises
  • Nutrition guides and support
  • Fitness test for customized plans
Features
Read full description

Every individual’s anatomy is different which is why we have designed a customizable, physical therapy approved core program. The iFour Core app addresses specific areas of your core to help you develop the strongest core imaginable without injury. Each workout is under 10 minutes, is suitable for all fitness levels, and can take place in the home or at the gym. As a member of the iFour Core app, you will receive new workouts every day, nutrition guides, and support. FREE 7-day trial for new members! HOW IT WORKS: After completing the iFour Core fitness test, you will get a core strength rating. This rating is broken up based on muscle fibers worked (intrinsic, rectus, obliques & transverse). The iFour Core app customizes the exercises each day based on your fitness test performance and current level of core strength. WHAT MAKES US DIFFERENT: Life is full of surprises, plateaus, and challenges. We created this app with this in mind allowing you to recalibrate your individualized workout formula at any point you feel necessary. Unlike other programs, this is not simply just hitting “reset,” and repeating the same exercises from previous days. This is a full recalculated algorithm taking you from your new “starting point” with a proven plan of attack to help you once again improve. iFour Core Features: Workout & Fitness Planning • Functional yet challenging core rotations, ranging from 5-10 Minutes! • Includes regressions to decrease difficulty and progressions to advance the exercises as you improve. • 323 unique core exercises. • 137 additional core exercises with 6 different pieces of equipment to choose from. • Video demonstrations of all 323 core exercises. • Designed for all levels, whether you are coming out of physical therapy or an elite athlete! • Take the fitness test and as you get stronger, unlock more core exercises prescribed for you. Tracking & Fitness Motivation • Workout along with J, a seasoned trainer for celebrities, professional athletes, and others. • Track your daily progress in both your Fitness Test and Workout History. • Share your results on your favorite social media platform. • Keep up to date and learn with the latest iFour videos. Subscription Pricing & Terms iFourCore is free to download. Ongoing use requires an active subscription, available on a monthly or annual basis. New customers are eligible for a 7-day free trial. Annual subscriptions are billed the total fee from the purchase date. Monthly subscriptions are billed per month. Payment will be charged to your credit card through your iTunes account at confirmation of purchase. Subscription renews automatically unless cancelled at least 24 hours prior to the end of the subscription period. There is no increase in price when renewing. Subscriptions can be managed and auto-renewal turned off in Account Settings in iTunes after purchase. Once purchased, refunds will not be provided for any unused portion of the term. Read our full Terms and Conditions & Privacy Policy: https://www.ifourlife.com/

About

Prehab U

Access personalized workout programs and track your fitness journey. Monitor workouts, nutrition, habits, and measurements with coach guidance. Connect with communities and earn badges for achievements.

Highlights
  • Access training plans and track workouts
  • Follow exercise and workout videos
  • Track meals and food choices
  • Monitor daily habits and progress
  • Message your coach in real-time
  • Join digital communities for motivation
  • Track body measurements and progress photos
Features
Read full description

With the Prehab U App, you will have access to workout programs designed specifically to help you reach your fitness and health goals! You can follow & track your workouts, your nutrition, your lifestyle habits, measurements and results–all with the help of your coach. FEATURES: - Access training plans and track workouts - Follow along to exercise and workout videos - Track your meals and make better food choices - Stay on top of your daily habits - Set health and fitness goals and track progress towards your goals - Gain milestone badges for achieving new personal bests and maintaining habit streaks - Message your coach in real-time - Be part of digital communities to meet people with similar health goals and stay motivated - Track body measurements and take progress photos - Get push notification reminders for scheduled workouts and activities - Connect your Apple Watch to track workouts, steps, habits, and more right from your wrist - Connect to other wearable devices and apps like the Apple Health App, Garmin, Fitbit, MyFitnessPal, and Withings devices to track workouts, sleep, nutrition, and body stats and composition Download the app today!

Screenshots

iFour Core4 screens
Prehab U4 screens

Verdict

The call

The clearest difference is in-app purchases: Prehab U at none against iFour Core's 2. Prehab U also leads on device support (4 vs 2). iFour Core's advantage is ratings volume (28 vs 4) and iOS requirement (11.0 vs 15.5). On price, rating, update cadence and ads 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. iFour Core sells 2 in-app purchases, starting at $5.99 per month. Prehab U asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for iFour Core against 5.0 for Prehab U. That said, the two scores are not equally well evidenced: iFour Core has 28 ratings behind it against 4, so its average is the more settled of the two.

UpkeepUpdate frequency

iFour Core ships an update every 2 months, Prehab U monthly. The most recent releases landed on September 17, 2026 and October 2, 2026 respectively.

Scorecard5 real differences · 5 level
iFour Core versus Prehab U: the parameters behind the verdict, then further details
ParameteriFour CorePrehab U
PriceFreeFree
Rating5.0 (28 ratings)5.0 (4 ratings)
Positive reviews100.0% of reviews—
Number of ratings28 — better4
Update frequencyEvery 2 monthsMonthly — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPodiPhone, iPad, iPod, Apple Watch — better
Requires iOS11.0 — better15.5
Further details — not scored
Size39 MB159 MB
Age rating4+4+
Developerifour.life, LLCAthletes Prehab LLC

Customer experience

iFour Core

All ratings28 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews11 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Prehab U

All ratings4 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

2 purchases

iFour Core

Subscriptions2
  • Monthly7 Days trial$5.991 Month
  • Annually7 Days trial$29.991 Year
None

Prehab U

No in-app purchases

Questions

Is iFour Core free?
iFour Core is free to download, with in-app purchases available.
Is Prehab U free?
Prehab U is free to download, with no in-app purchases.
Which has better reviews, iFour Core or Prehab U?
iFour Core and Prehab U are both rated 5.0 out of 5 on the App Store, from 28 and 4 ratings respectively.
Do iFour Core or Prehab U have ads?
Neither iFour Core nor Prehab U shows ads.
Which is updated more often, iFour Core or Prehab U?
iFour Core ships an update every 2 months, and Prehab U monthly. Most recently, iFour Core was updated on September 17, 2026 and Prehab U on October 2, 2026.

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