Comparison

Zero vs STARK

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

Head to head
About

Zero

Features
Read full description

ZERO-G transforms your daily workouts into immersive mission days aboard the Mothership. Each morning you’re briefed on a critical system failureβ€”then complete 6 focused missions (Strength, Endurance, Mobility, Stability, Balance, Recovery) to stabilize the ship and keep the crew alive. What makes ZERO-G different? Camera Vision – on-device pose detection for form checks, rep counting, and posture alignment. Earn a Form Clean badge when your technique is safe and strong. Personal AI Coach – natural voice briefings keep the mission moving, give real-time cues during sets, answer quick questions, and motivate you hands-free. AI-generated missions – every day brings a fresh storyline, dynamically created from real astronaut training and spacecraft incidents. Talk to Mothership – your AI companion for guidance, motivation, or just everyday questions. Drift Mode – precision warm-up exercises powered by iPhone gyroscope and accelerometer. Challenge Mode – multiplayer duels where you compete with other users in real time. Points & Streaks – earn G Points for every task and keep your streak alive to rise through crew ranks. Mission Log & Calendar – review your completed missions, track missed days, and celebrate personal records. Smart Notifications – daily reminders and community event alerts keep you engaged. How a day works Briefing – the Mothership reports today’s crisis. Pre-brief context – why the mission matters and what you’ll do. Mission – e.g. Hydraulic Squats (15 reps, 40s). Camera overlay tracks joints, AI coach gives live cues. Debrief – instant points, streak updates, and rank progress. Subscription Information ZERO-G requires a subscription to unlock premium features. Title: ZERO-G Subscription Length: 1 Month / 1 Year Payment will be charged to your Apple ID account at confirmation of purchase. Subscription automatically renews unless canceled at least 24 hours before the end of the current period. Account will be charged for renewal within 24 hours prior to the end of the current period. You can manage or cancel your subscription in your App Store account settings after purchase. Privacy Policy: https://zero-g.app/privacy Terms of Use: https://zero-g.app/terms Disclaimer ZERO-G provides general fitness guidance and is not a medical app. Always consult a healthcare professional before starting any new exercise program. All camera analysis runs locally on your device. No workout videos are uploaded or stored externally.

About

STARK

Log your weightlifting sessions, track personal records, and plan custom routines. Features animated exercise demos, rest timers, and progress visualization. Integrates with Apple Health and Apple Watch for comprehensive fitness tracking.

Highlights
  • Log sets, reps, and weights
  • Supersets and drop sets support
  • Rest timer with notifications
  • Animated exercise demos
  • Build custom workout programs
  • Track progress and personal records
  • Apple Health and Watch integration
Features
Read full description

Log your sets, track your weights and follow your personal records with STARK, your gym workout tracker for iPhone and Apple Watch. Plan your routines and see your progress, workout after workout. LOGGING WITHOUT FRICTION β€’ Exercises, sets, reps, weights and notes, entered in a few taps. β€’ Supersets, warm-up sets, drop sets, per-side entry. β€’ Help counting the weight loaded on the bar. β€’ Rest timer with notification: the alert fires even with the screen locked. β€’ Train together with a friend. β€’ Cardio logged in the same place as lifting. β€’ Interrupted workouts resume automatically. 1,394 EXERCISES β€’ Animated demo and form cues for every movement. β€’ Filter by muscle, level and equipment, and by machine brand to find the gear at your gym. β€’ Add your own exercises. PROGRAMS β€’ Build your own programs, or generate a workout for your time and equipment. β€’ Organize programs, workouts and exercises in folders. β€’ A first-workout guide to get you started. YOUR PROGRESS β€’ History per exercise, personal records, volume per muscle group. β€’ Muscle balance: what you train, and what you skip. β€’ Body weight tracking and progress photos. APPLE HEALTH AND APPLE WATCH β€’ Finished workouts are saved to Apple Health. β€’ Body weight and heart rate are read from Health if you allow it. β€’ The Apple Watch app shows the current set and starts your rest from the wrist. WITH FRIENDS β€’ Add friends, see their finished workouts, react and comment. β€’ Report and block any content posted by another account. SWITCH APPS WITHOUT LOSING ANYTHING Import your history from another lifting app (CSV file): exercises are matched to the catalog, and importing the same file again never creates duplicates. NO ACCOUNT NEEDED Start right away as a guest. Creating an account keeps the workouts you've already logged and syncs them across devices. STARK+ The STARK+ subscription unlocks the full program catalog, the unlimited generator, the adaptive coach that suggests weight changes, in-depth analytics (estimated 1RM, sets per muscle, weekly review), unlimited chart history, unlimited custom exercises, plus extra themes and icons. It also funds the app, built by a single developer. The subscription renews automatically unless cancelled at least 24 hours before the end of the current period. Manage or cancel it from your App Store account. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ STARK Terms: https://starkworkout.app/terms-of-use Privacy Policy: https://starkworkout.app/privacy-policy

Screenshots

Zero4 screens
STARK4 screens

Verdict

The call

Zero and STARK are too close to call on the numbers: across 6 compared parameters β€” price, update cadence, ads and in-app purchases among them β€” neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

Scored on Price Β· Rating Β· Positive reviews Β· Number of ratings Β· Update frequency Β· Ads Β· In-app purchases Β· Monetization Β· Best chart rank Β· Devices Β· Requires iOS

CostPrice Β· In-app purchases Β· Ads Β· Monetization

Both are free to download. Zero sells 2 in-app purchases, starting at $9.99 per month and STARK sells 2 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 3 days. The most recent releases landed on October 30, 2026 and November 1, 2026 respectively.

ScorecardNo meaningful differences
Zero versus STARK: the parameters behind the verdict, then further details
ParameterZeroSTARK
PriceFreeFree
Positive reviewsβ€”100.0% of reviews
Update frequencyEvery 3 daysEvery 3 days
AdsNoNo
In-app purchasesYesYes
Monetizationβ€”Freemium
DevicesiPhoneiPhone, Apple Watch β€” better
Requires iOS18.117.0 β€” better
Further details β€” not scored
Size56 MB94 MB
Age rating4+4+
DeveloperBARTOSZ IDZIK,AXEL PIERRE HUGO SAILLARD

In-app purchases

2 purchases

Zero

Subscriptions2
  • Monthly3 Days trial$9.991 Month
  • Annual3 Days trial$79.991 Year
2 purchases

STARK

Subscriptions2
  • Stark Premium Monthly7 Days trial$4.991 Month
  • STARK Premium Yearly7 Days trial$39.991 Year

Questions

Is Zero free?
Zero is free to download, with in-app purchases available.
Is STARK free?
STARK is free to download, with in-app purchases available.
Do Zero or STARK have ads?
Neither Zero nor STARK shows ads.
Which is updated more often, Zero or STARK?
Zero ships an update every 3 days, and STARK every 3 days. Most recently, Zero was updated on October 30, 2026 and STARK on November 1, 2026.

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