Comparison

쪽잠 Pro vs ShiftRhythm

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

Head to head
About

쪽잠 Pro

This app provides a quiet nap timer for short rests, allowing custom duration settings. It plays alarms only through earphones for discreet use in quiet environments and displays remaining time on the lock screen and Dynamic Island.

Highlights
  • Custom nap time setting
  • Quick selection for common durations
  • Earphone-only alarm playback
  • Lock screen and Dynamic Island display
  • Adjustable system volume within the app
  • 5-minute interval repeat alarm
Features
Read full description

쪽잠 Pro는 짧은 낮잠과 휴식을 위한 조용한 쪽잠 타이머입니다. 유튜브 영상은 정해진 길이에 맞춰 들어야 하지만 쪽잠 Pro에서는 원하는 시간을 직접 설정할 수 있습니다. 5분, 15분, 30분처럼 자주 쓰는 시간은 바로 선택하고 필요한 경우 시간·분·초를 직접 조절해 나에게 맞는 쪽잠 시간을 만들 수 있어요. 이어폰을 연결하면 알람음이 이어폰으로 재생되어 독서실, 도서관, 사무실처럼 조용한 공간에서도 사용할 수 있습니다. 시스템 볼륨 슬라이더를 앱 안에서 바로 조절할 수 있어 알람이 들릴 정도로 미리 맞춰둘 수 있습니다. 잠금화면과 Dynamic Island에서는 남은 시간을 확인할 수 있고, 5분 간격 반복 기능을 켜두면 앱에서 알람을 끄기 전까지 다시 울리도록 설정할 수 있습니다. 주요 기능 - 원하는 쪽잠 시간 직접 설정 - 자주 쓰는 시간 빠른 선택 - 일어날 시간 기준 알람 설정 - 이어폰으로 조용한 알람 재생 - 앱 안에서 시스템 볼륨 조절 - 잠금화면 및 Dynamic Island 남은 시간 표시 - 5분 간격 반복 알람 - 처음 사용하는 사람을 위한 튜토리얼 주의 앱을 완전히 종료하지 않고 백그라운드에 둔 상태에서 사용해주세요. 기기 또는 이어폰의 시스템 볼륨이 0이면 알람음이 들리지 않을 수 있습니다.

About

ShiftRhythm

This app helps night shift workers optimize their sleep and light exposure based on their unique roster. It provides personalized guidance for sleep, naps, and light timing to align with your body clock and manage sleep debt.

Highlights
  • Personalized sleep and nap timing
  • Light exposure guidance
  • Circadian rhythm dial
  • Sleep score and debt tracking
  • Roster presets and custom schedules
  • Apple Watch app and widgets
Features
Read full description

Night shifts flipped your sleep? Enter your roster and ShiftRhythm tells you when to sleep, when to nap, and when to seek or avoid light — today. WHAT IT DOES • 24-hour body-clock dial — see your estimated melatonin onset (DLMO) and biological night (CBTmin) at a glance • Light, nap & caffeine guidance — timed to your circadian rhythm and updated as your shifts change • Sleep score, sleep debt & recovery — last night's sleep plus HRV and resting heart rate from Apple Watch, telling you whether to push or recover • Presets that match real rosters — Panama 2-2-3 schedule (day/night), Pitman, DuPont, Fire 48/96, 12-hour rotating shifts, plus Korean and Japanese patterns. Or build your own custom rotation • Melatonin timing card (optional) — an informational window based on your estimated body clock. Not a recommendation to take melatonin; talk to your doctor or pharmacist first BUILT FOR SHIFT WORKERS Whether you're a night shift nurse, a firefighter on 48/96, a plant operator on a DuPont rotation, or a driver on a rotating roster — ShiftRhythm adapts to your schedule, not the other way around. • Tap any calendar day to correct that day's shift • Works from your schedule alone — no Apple Watch required • Apple Watch app and widgets included; available in English, Spanish, Korean, and Japanese PRIVATE BY DESIGN • No account. No server. Your data stays on your phone. • All circadian math runs on-device — health data never leaves your iPhone • No ads, no tracking PRICING • 30-day free trial — full features, no account needed • Then Monthly or Annual (Annual saves vs. monthly), or a one-time Lifetime purchase if you'd rather not subscribe • Subscriptions auto-renew; cancel anytime in Settings > Apple Account > Subscriptions Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://yoonspower.github.io/shiftrhythm/privacy.html ShiftRhythm is for general wellness and reference only. It is not a medical device and does not diagnose, treat, or monitor any medical condition. Values shown are estimates and may be inaccurate. Consult a professional for health concerns.

Screenshots

쪽잠 Pro4 screens
ShiftRhythm4 screens

Verdict

The call

The clearest difference is in-app purchases: 쪽잠 Pro at none against ShiftRhythm's 3. ShiftRhythm's advantage is update cadence (every 2 days vs every 3 weeks) and device support (3 vs 1). On price, review sentiment, ads 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. ShiftRhythm sells 3 in-app purchases, starting at $2.99 per month. 쪽잠 Pro asks for nothing beyond the download.

UpkeepUpdate frequency

쪽잠 Pro ships an update every 3 weeks, ShiftRhythm every 2 days. The most recent releases landed on October 12, 2026 and October 8, 2026 respectively.

Scorecard4 real differences · 6 level
쪽잠 Pro versus ShiftRhythm: the parameters behind the verdict, then further details
Parameter쪽잠 ProShiftRhythm
PriceFreeFree
Rating3.8 (4 ratings) — better—
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings4 — better—
Update frequencyEvery 3 weeksEvery 2 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhoneiPhone, iPad, Apple Watch — better
Requires iOS17.017.0
Further details — not scored
Size9 MB16 MB
Age rating4+4+
DeveloperYechan GuJaeyoun Kim

Customer experience

쪽잠 Pro

Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

ShiftRhythm

Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

쪽잠 Pro

No in-app purchases

3 purchases

ShiftRhythm

Subscriptions2
  • Monthly$2.991 Month
  • Yearly$14.991 Year
One-time1
  • Lifetime$39.99

Questions

Is 쪽잠 Pro free?
쪽잠 Pro is free to download, with no in-app purchases.
Is ShiftRhythm free?
ShiftRhythm is free to download, with in-app purchases available.
Do 쪽잠 Pro or ShiftRhythm have ads?
Neither 쪽잠 Pro nor ShiftRhythm shows ads.
Which is updated more often, 쪽잠 Pro or ShiftRhythm?
쪽잠 Pro ships an update every 3 weeks, and ShiftRhythm every 2 days. Most recently, 쪽잠 Pro was updated on October 12, 2026 and ShiftRhythm on October 8, 2026.

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