Comparison

Zero vs OutTime

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

Head to head
About

Zero

Features
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ZERO-G transforms your daily workouts into immersive mission days aboard the Mothership. Each morning you’re briefed on a critical system failure—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

OutTime

This app helps you track your clear aligner wear time by counting down your daily out-time budget. It offers hands-free Siri control, session editing, and keeps all your data private on your device. Pro features include wrist and Lock Screen countdowns, and timelapse videos.

Highlights
  • Countdown out-time budget
  • Hands-free Siri control
  • Edit past sessions
  • Private, on-device data
  • Apple Watch integration
  • Lock Screen Live Activities
  • Retainer mode
Features
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Most aligner apps count up. OutTime counts down, so you always know exactly how much out-time you have left today. Free to use, with a one-time Pro upgrade and no subscription. OutTime is a personal timer and does not provide medical advice. Always follow your orthodontist's instructions. Pro adds the Apple Watch app, Home Screen widgets, full stats history, and more for a single $9.99 purchase. No account, no ads, Family Sharing included. Works with Invisalign, Angel Aligner, Spark, ClearCorrect, Byte, and any other clear aligner. A BUDGET, NOT A STOPWATCH A stopwatch leaves you to do the math. OutTime gives you a daily out-time budget and counts it down every time your aligners come out. Tap once when your aligners come out, tap again when they go back in. SEE WHERE YOUR OUT-TIME GOES Where do your two hours go? OutTime sorts your sessions into Food, Drink, Meetings, and more, with your session count, average, and longest. See your 7-day average next to last week's, and days on budget for every tray. Tap any day in the month calendar to see that day's sessions, or log one you forgot. With Pro, share a clean Wear-Time Summary PDF of any month, plus your session data as CSV, ready for your next appointment. PRO: ON YOUR WRIST AND HOME SCREEN Start and end sessions from your Apple Watch, and see your remaining out-time on your wrist. Home Screen widgets show it all day. While your aligners are out, the countdown also runs on your Lock Screen. FORGOT TO START THE TIMER? Edit any session after the fact: adjust the time or duration, or log a session you missed entirely. Life happens; your data should still be accurate. HANDS-FREE WITH SIRI Hands full at lunch? Say "Take my aligners out with OutTime" to start a session, or "Put my aligners back in with OutTime" to end it. Works with Shortcuts and the Action Button too. YOUR DATA STAYS YOURS No account. No email. No OutTime server. Zero analytics. Zero data collected. Everything lives on your iPhone. Optional iCloud Backup & Restore (Pro) keeps a copy in your own private iCloud so you can restore on a new iPhone, and we still cannot see it. The App Store privacy label says "Data Not Collected." We mean it. SMILE TIMELINE Build a private photo timeline of your smile, tray by tray. Crop, straighten, rotate, and brighten each photo. Put any two side by side and share them, or turn the whole timeline into an MP4 timelapse video. Your first photo is free. Pro unlocks the rest. RETAINER MODE Treatment ends, but retainers do not. Pick "I wear a retainer" on first launch, or switch later. Full-time or nights-only wear, with its own bedtime and replacement reminders. MADE BY ONE DEVELOPER No investors, no ads, no data sold. Pro is the only thing funding OutTime, so your purchase pays for the updates and the support replies. OUTTIME PRO - PAY ONCE, NO SUBSCRIPTION Your countdown, at a glance - Apple Watch app - Home Screen widgets - Lock Screen countdown during out-time sessions Your history, all of it - Full stats history: every month and every tray, back to day one - Smile Timeline: unlimited photos, side-by-side sharing, MP4 timelapse - Export for your orthodontist: Wear-Time Summary PDF, CSV data, photos Reminders, icons & backup - Cleaning and appointment reminders - Alternate app icons: six quieter looks - iCloud Backup & Restore: optional, off by default FREE - Full countdown timer with daily budget - Activity tagging (Food, Drink, Meeting, Brush, Exercise, Other) - Break Types stats: see where your out-time goes - 7-day average and current + previous tray stats - Your last 30 days of stats and calendar, day by day - Every session you have ever logged, in View All History - Hands-free Siri voice commands - Tray calendar: extend, delay, and set the days for each tray - Out-time and tray change reminders - Your first Smile Timeline photo For informational purposes only. Follow your orthodontist's guidance.

Screenshots

Zero4 screens
OutTime4 screens

Verdict

The call

The clearest difference is update cadence: Zero at every 3 days against OutTime's weekly. On price, ads, in-app purchases and device support 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. Zero sells 2 in-app purchases, starting at $9.99 per month and OutTime sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Zero ships an update every 3 days, OutTime weekly. The most recent releases landed on October 1, 2026 and October 3, 2026 respectively.

Scorecard1 real difference · 9 level
Zero versus OutTime: the parameters behind the verdict, then further details
ParameterZeroOutTime
PriceFreeFree
Rating—4.1 (8 ratings) — better
Positive reviews—100.0% of reviews
Number of ratings—8 — better
Update frequencyEvery 3 days — betterWeekly
AdsNoNo
In-app purchasesYesYes
Monetization—Freemium
DevicesiPhoneiPhone, Apple Watch — better
Requires iOS18.1 — better18.4
Further details — not scored
Size56 MB6 MB
Age rating4+4+
DeveloperBARTOSZ IDZIKEmil Georgiev

In-app purchases

2 purchases

Zero

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

OutTime

One-time1
  • OutTime Pro$9.99

Questions

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

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