Comparison

StrengthLog vs KAI Skin

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

Head to head
About

StrengthLog

Track your workouts, analyze progress, and discover proven strength training programs. Log unlimited workouts, access a vast exercise library, and set goals. Upgrade for advanced statistics and premium programs.

Highlights
  • Unlimited workout logging
  • Extensive exercise library with video instructions
  • Proven strength training programs
  • Progress analysis and statistics
  • Goal setting and streak tracking
  • Plate calculator and rest timer
  • Apple Health integration
Features
Read full description

THE WORLD’S MOST GENEROUS WORKOUT TRACKER StrengthLog is the workout tracker for people who take their training seriously, whether you’re just getting started or have been lifting for decades. Plan your training. Log every set. Track your progress. Follow proven training programs or build your own. Compare your strength with other lifters. Set goals, build streaks, and challenge your friends. And unlike many workout apps, StrengthLog gives you everything you need to train effectively for free. Unlimited workout logging. No ads. No trial that suddenly locks you out. 100% gains, 0% ads. BUILT FOR LIFTERS, BY LIFTERS StrengthLog has been developed together with hundreds of thousands of lifters, from beginners to competitive strength athletes. Our library contains 600+ strength, cardio, and mobility exercises with instructions and videos. You can also create your own exercises. Log as you train or plan ahead with our calendar. Follow a ready-made training program, build your own, or simply decide what to do when you get to the gym. Your training history, PRs, statistics, and Strength Levels make it easy to see where you’ve been and where you’re going. TRAIN TOGETHER Connect with friends and make your training a little more social. See when your friends train, celebrate their progress, compare PRs and Strength Levels, and create or join challenges together. Challenge each other to train more often, do more reps, or reach whatever ridiculous goal you can come up with. You choose who you connect with, and your full training log stays private. FREE FEATURES • Log unlimited workouts, forever. • Support for both kg and lbs. • 600+ exercises with instructions and videos. • Create unlimited custom exercises. • Follow popular workouts and training programs. • Build your own routines and programs with linear progression. • Plan workouts and programs in your training calendar. • Track PRs and exercise history. • Compare your strength with other lifters using Strength Levels. • Track training volume, workouts, and other statistics. • Create training goals and streaks. • Complete our monthly challenges. • Connect with friends and challenge each other. • Use our rest timer and plate calculator. • Estimate your 1RM and get suggested PR warm-ups. • Track body measurements and progress pictures. • Connect with Apple Health. GO PREMIUM StrengthLog Premium unlocks our most advanced tools while supporting the continued development of the app. Premium includes: • Build unlimited training routines and programs with double and triple progression. • Our complete library of training programs for strength, bodybuilding, powerlifting, powerbuilding, sports, and more. • Advanced statistics for your training, muscle groups, and exercises. • Muscle heat maps showing what you’ve trained over any period. • Customizable favorite graphs. • Advanced logging with RPE, Reps in Reserve, % of 1RM, and quick set stats. • More tools for analyzing and planning your training. • Unlimited goals and streaks. • Connect your account to ChatGPT or Claude using our MCP integration. Whether you want a simple workout log or enough training data to disappear down a statistical rabbit hole for an entire evening, StrengthLog has you covered. Have an idea, found a bug, or just want to tell us what you think? Contact us at app@strengthlog.com. SUBSCRIPTIONS StrengthLog Premium is an automatically renewing subscription. • Choose between 1, 3, and 12 months. • Your App Store account will be charged upon purchase and your subscription will renew automatically unless canceled at least 24 hours before the end of the current period. • You can manage or turn off auto-renewal in your App Store account settings. APPLE HEALTH With your permission, StrengthLog can read relevant data from Apple Health and share your completed workouts with it. You control what data StrengthLog can read or write through your Apple Health permissions.

About

KAI Skin

Features
Read full description

KAI Skin helps you understand your skin and build a routine you can stick to. Take a photo to get an AI-powered skin score and insights, choose what you want to focus on, then generate a personalized morning and evening routine. Terms of Service: https://sites.google.com/view/kaiskin/privacy?#h.vcr6nf8mev05 Privacy Policy: https://sites.google.com/view/kaiskin/privacy?authuser=0

Screenshots

StrengthLog4 screens
KAI Skin4 screens

Verdict

The call

The clearest difference is update cadence: StrengthLog at every 6 days against KAI Skin's every 5 months. StrengthLog also leads on device support (4 vs 1). On price, ads, in-app purchases 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. StrengthLog sells 3 in-app purchases, starting at $16.90 per month and KAI Skin sells 2 in-app purchases, starting at $12.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

StrengthLog ships an update every 6 days, KAI Skin every 5 months. The most recent releases landed on October 24, 2026 and October 3, 2026 respectively.

Scorecard2 real differences · 8 level
StrengthLog versus KAI Skin: the parameters behind the verdict, then further details
ParameterStrengthLogKAI Skin
PriceFreeFree
Rating4.9 (3.7K ratings) — better—
Positive reviews88.0% of reviews—
Number of ratings3.7K — better—
Update frequencyEvery 6 days — betterEvery 5 months
AdsNoNo
In-app purchasesYesYes
MonetizationFreemium—
DevicesiPhone, iPad, iPod, Apple Watch — betteriPhone
Requires iOS15.0 — better16.6
Further details — not scored
Size158 MB16 MB
Age rating12+4+
DeveloperStyrkelabbet ABALI ATAEI FARD

Bugs and requests

StrengthLog

Reported bugs

3 issues
  • Disappearing workout data
  • Inability to clear/reset workout history
  • Inconsistent behavior when planning workouts for the same day

Requested features

4 requests
  • Ability to save and edit custom workout plans
  • Seamless integration with Apple Health
  • Community features like challenges and leaderboards
  • More personalized workout recommendations

KAI Skin

Not enough reviews yet to summarise bugs or requests.

In-app purchases

3 purchases

StrengthLog

Subscriptions3
  • StrengthLog Premium - 1 month14 Days trial$16.901 Month
  • StrengthLog Premium - 3 months14 Days trial$37.903 Months
  • StrengthLog Premium - 1 year14 Days trial$109.001 Year
2 purchases

KAI Skin

Subscriptions2
  • Premium Monthly$12.991 Month
  • Premium Yearly$39.991 Year

Questions

Is StrengthLog free?
StrengthLog is free to download, with in-app purchases available.
Is KAI Skin free?
KAI Skin is free to download, with in-app purchases available.
Do StrengthLog or KAI Skin have ads?
Neither StrengthLog nor KAI Skin shows ads.
Which is updated more often, StrengthLog or KAI Skin?
StrengthLog ships an update every 6 days, and KAI Skin every 5 months. Most recently, StrengthLog was updated on October 24, 2026 and KAI Skin on October 3, 2026.

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