Comparison

KneeFit vs re.flex

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

Head to head
About

KneeFit

Strengthen and stretch your knees with daily exercises designed to promote knee health and fitness. This app is suitable for active individuals, those undergoing therapy, or anyone looking to maintain an active lifestyle.

Highlights
  • Strength exercises
  • Stretch exercises
  • Daily routines
  • Knee health maintenance
  • Therapy support
  • Fitness lifestyle integration
Features
Read full description

Keep your knee strong and healthy by using the strength and stretch exercises in the KneeFit App. Doing a few exercises daily will keep your knee healthy and fit. As an active individual, I use the exercises in KneeFit before and after my workouts. Whether you are going through therapy, recovering, or maintaining an active fitness lifestyle the KneeFit App is for you.

About

re.flex

This app helps you recover from joint pain at home with medically validated exercises. It uses patented sensor technology for accurate movement tracking and provides real-time feedback to improve exercise execution. Detailed reports track your progress and pain levels.

Highlights
  • Medically validated exercise programs
  • Patented sensor technology for movement tracking
  • Real-time acoustic and 3D visual feedback
  • Personalized digital exercise assistant
  • Detailed training and progress reports
  • Flexible training scheduling
Read full description

re.flex supports you to actively recover from your joint pain at home. It is aimed in particular at users with osteoarthritis of the knee and hip joints. The patented sensor technology developed by us specifically for exercise therapy enables the minutely accurate tracking of your movements and provides you with almost latency-free feedback on the quality and quantity of the execution of your movements. IMPORTANT: To be able to train with re.flex, you need (a) a sensor kit and (b) an activation code. Health insurance in Germany: Sensor Kit: You will receive the sensor kit from our German distribution partner. After you create your account in the app, you will receive an order form for the sensor kit via email. Activation code: If you have statutory health insurance, you will receive the activation code from your health insurance company. If you are privately insured, you will get the unlock code from our distribution partner. NO health insurance in Germany: Contact us at info@reflex.help to find out how to get the sensor kit and activation code. re.flex at a glance - Medically validated - The exercise programs have been developed in cooperation with the most renowned universities in sports medicine. They are based on the current state of the art in physical therapy as well as current study-based guidelines to ensure you the highest possible quality standard. - Proven exercises - The exercise programs include simple exercises to improve your strength, flexibility and motor skills as well as reduce your joint pain. Personal Exercise Assistant - With re.flex, you get a personal digital exercise assistant that interactively guides you through the exercises with clear instructions. - Objective measurement of movement - Using movement sensors, re.flex is able to give you immediate live feedback on whether you are performing the exercise correctly or incorrectly. You receive both acoustic and visual feedback in 3D. - 3D Visual Feedback - 3D visual feedback gives you detailed information about your own movement in space and clear instructions on how to perform the exercise. - Audible Feedback - Audible feedback allows you to perform your exercises "hands-off" if you already know how to do the exercise. - Positive behavioral correction - Correct behavior is positively reinforced, and incorrect behavior is given specific instructions on how to perform the exercise correctly. - Detailed training reports - re.flex provides you detailed graphical reports on various aspects of your training. For example, you can track the progress of your training fidelity, the development of pain and also qualitative metrics such as the execution accuracy of your exercises. Thus, the training report provides both you and the doctor (in case you want to share your report with your doctor) with objective transparency about your training progress. - Flexible training time - re.flex allows you to choose the time and place of your training week. If you miss a workout, you will be reminded automatically. Missed workouts can be made up on break days to prevent both under- and overtraining. - Flexible training routine - If the patient is unable to perform an exercise, the workout program always provides alternative exercises, or the option to skip the exercise if necessary. Health insured in Germany: Mail: digital@sporlastic.de Tel: +49 7022 705 181 Business hours: Monday to Thursday 8:00 – 17:00 and Friday 8:00 – 16:00 Not health insured in Germany: Web: www.reflex.help Mail: info@reflex.help

Screenshots

KneeFit2 screens
re.flex4 screens

Verdict

The call

The clearest difference is update cadence: re.flex at every 3 weeks against KneeFit's every 71 months. KneeFit's advantage is ratings volume (4 vs 1). On price, rating, ads and in-app purchases 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. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for KneeFit against 5.0 for re.flex. Both are backed by a comparable volume of ratings — 4 and 1 respectively.

UpkeepUpdate frequency

KneeFit ships an update every 71 months, re.flex every 3 weeks. The most recent releases landed on October 7, 2026 and October 3, 2026 respectively.

Scorecard2 real differences · 8 level
KneeFit versus re.flex: the parameters behind the verdict, then further details
ParameterKneeFitre.flex
PriceFreeFree
Rating5.0 (4 ratings)5.0 (1 ratings)
Positive reviews100.0% of reviews—
Number of ratings4 — better1
Update frequencyEvery 71 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS13.012.0 — better
Further details — not scored
Size4 MB231 MB
Age rating4+4+
DeveloperAlex PaulKineto Tech Rehab

Customer experience

KneeFit

All ratings4 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

re.flex

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

KneeFit

No in-app purchases

None

re.flex

No in-app purchases

Questions

Is KneeFit free?
KneeFit is free to download, with no in-app purchases.
Is re.flex free?
re.flex is free to download, with no in-app purchases.
Which has better reviews, KneeFit or re.flex?
KneeFit and re.flex are both rated 5.0 out of 5 on the App Store, from 4 and 1 ratings respectively.
Do KneeFit or re.flex have ads?
Neither KneeFit nor re.flex shows ads.
Which is updated more often, KneeFit or re.flex?
KneeFit ships an update every 71 months, and re.flex every 3 weeks. Most recently, KneeFit was updated on October 7, 2026 and re.flex on October 3, 2026.

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