Comparison

Grey Matter Training vs CORE4 Members

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

Head to head
About

Grey Matter Training

This app offers personalized, science-backed training, nutrition, and supplement guidance for competitive athletes and fitness enthusiasts. It requires a paid coaching plan to access its full features.

Highlights
  • Individualized training plans
  • Evidence-based nutrition guidance
  • Supplementation strategies
  • For physique and strength athletes
  • For training enthusiasts
Features
Read full description

Grey Matter Training is a service providing individualized, evidence-based training, nutrition, and supplementation plans for competitive physique athletes, strength athletes, and training enthusiasts alike. *Requires paid coaching plan Terms of use: https://kahunas.io/terms-conditions Privacy policy: https://kahunas.io/privacy

About

CORE4 Members

Features
Read full description

The CORE4 Members App by Coach Caelum The CORE4 Members App is a private coaching platform designed for men who want structured progress without noise, gimmicks, or guesswork. The app supports a highly personalised online coaching experience built around The CORE4 Habit Acquisition System, combining training, nutrition, recovery, and lifestyle habits into a single, guided system. Everything inside The CORE4 Members App is tailored to the individual and adjusted as real-world feedback comes in. This is not a collection of generic plans. It’s a place where strategy is applied, refined, and maintained over time. What The CORE4 Members App helps you do: Train with structure and intent - Access your personalised workout plan, designed around your goals, current ability, and recovery capacity. Each phase is adjusted as your body adapts, ensuring training remains effective and sustainable. Manage nutrition without unnecessary restriction - Follow a clear nutrition structure that supports fat loss, performance, and long-term adherence. Plans are built to fit real lifestyles and evolve based on progress, energy, and feedback. Build habits that support results - Track daily behaviours such as steps, sleep, hydration, and consistency. These habits form the foundation that keeps progress moving outside the gym. Stay connected through in-app coaching - Communicate directly with your coach through in-app messaging. Weekly check-ins allow feedback to be reviewed and plans refined with precision. See the bigger picture - The CORE4 Members App brings training, nutrition, recovery, and mindset into one place, making it easier to stay consistent and understand how each piece supports your progress. Designed for long-term progress The CORE4 Members App is built for those who value clarity, structure, and guidance. The focus is not on quick fixes, but on creating a system that can be maintained, adjusted, and progressed over time. Access to The CORE4 Members App is provided as part of the online coaching experience with Coach Caelum. Apply online to gain access. *App access requires a paid coaching plan. Terms Of Use: https://kahunas.io/terms-conditions Privacy Policy: https://kahunas.io/privacy Medical Disclaimer: This app does not provide medical advice, diagnoses, or treatment. The information and guidance provided within the app are for general fitness and wellbeing purposes only. Always seek the advice of your physician or other qualified healthcare provider before starting any exercise program, changing your nutrition, or making decisions regarding your health.

Screenshots

Grey Matter Training3 screens
CORE4 Members3 screens

Verdict

The call

Grey Matter Training and CORE4 Members are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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. Grey Matter Training sells 1 in-app purchase, starting at $399.99 per month and CORE4 Members sells 1 in-app purchase, starting at $299.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly monthly. The most recent releases landed on October 15, 2026 and October 17, 2026 respectively.

ScorecardNo meaningful differences
Grey Matter Training versus CORE4 Members: the parameters behind the verdict, then further details
ParameterGrey Matter TrainingCORE4 Members
PriceFreeFree
Rating5.0 (3 ratings) — better—
Number of ratings3 — better—
Update frequencyMonthlyMonthly
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.015.0
Further details — not scored
Size47 MB57 MB
Age rating17+4+
DeveloperMichael WhiteCoach Caelum

In-app purchases

1 purchases

Grey Matter Training

Subscriptions1
  • Monthly Coaching$399.991 Month
1 purchases

CORE4 Members

Subscriptions1
  • The CORE4 Framework$299.991 Month

Questions

Is Grey Matter Training free?
Grey Matter Training is free to download, with in-app purchases available.
Is CORE4 Members free?
CORE4 Members is free to download, with in-app purchases available.
Do Grey Matter Training or CORE4 Members have ads?
Neither Grey Matter Training nor CORE4 Members shows ads.
Which is updated more often, Grey Matter Training or CORE4 Members?
Grey Matter Training ships an update monthly, and CORE4 Members monthly. Most recently, Grey Matter Training was updated on October 15, 2026 and CORE4 Members on October 17, 2026.

Other comparisons