# Jet Lag: Both Clocks — Time zone shift for travel

> Time zone shift for travel (iPhone/iPad app by Jinwan Kim.)

- Source: https://appshunter.io/ios/app/jet-lag-both-clocks/id6809072410 (this page in markdown: same URL + `.md`)
- Developer: [Jinwan Kim](https://appshunter.io/developer/1446513824)
- Category: Travel, Utilities
- Price: Free
- Age rating: 4+
- Requires: iOS 17.0 · 4 MB
- Languages: American English, French (France), German (Germany), Japanese, Korean, European Spanish, Chinese (Traditional, Taiwan)
- Released: 2026-09-15
- Data updated: 2026-10-09
- User reviews in markdown: https://appshunter.io/ios/app/jet-lag-both-clocks/id6809072410/reviews.md

## What is Jet Lag?

Both clocks on every line.

A jet lag plan is a list of moments, and a moment has two names: what time it is at home and what time it is where you are going. This one writes both on every single line, together with both dates, so a three in the morning bedtime is pinned to the right night. Crossing the Pacific, the destination is often still on yesterday's date, and that is exactly the half other timetables drop.

It goes whichever way needs fewer days.

Turning your clock the short way round is not always the fast way. Going later moves further per day than going earlier, so a thirteen hour gap westward can finish in nine days while an eleven hour gap eastward takes eleven. The app compares days, not hours, and tells you on the first screen what the other direction would have cost.

Times and nothing else.

Bedtime, wake, when to seek light, when to avoid it, and the hour after which coffee stops. That is the whole plan. Nothing to take, nothing to wear, nothing to buy for the trip and no promise about how you will feel.

No flight number, no account, no signal.

Give it two cities and two local times. There is nothing to look up, so the plan opens at thirty thousand feet with the radio off. If the departure slips, correct the two times yourself and the timetable is rebuilt from the moment you are in.

Every number is on one page, and every one is yours.

Minutes per day going earlier, minutes per day going later, how long before waking the body's low point sits, how long a light window runs, how many hours before bed the coffee stops. Each one says where it came from and each one has a stepper next to it. Six presets set them all at once, from gentle to crew pace.

Ninety-two cities, and the offsets come from your phone.

Picking a city only fills in a time zone. The offset itself is read from this device for the dates you are flying, so a summer time change in the middle of a trip is already in the plan.

Out and back are two trips.

The way home is almost never the same number of days, so it gets its own plan. Everything is saved on this device, with no account to make and nothing to restore.

The timetable is plain typed characters, so it drops straight into a message rather than arriving as a file.

Languages: English, 한국어, 日本語, 繁體中文, Deutsch, Français, Español


## Version history (last 1 release)

### 1.0 — 2026-09-16

No release notes.

## More apps by Jinwan Kim

- [One Thing Today: Daily Goal](https://appshunter.io/ios/app/one-thing-today-daily-goal/id1446513825)
- [Five Shapes](https://appshunter.io/ios/app/five-shapes/id1448811518)
- [BrightPocket: Compliment Log](https://appshunter.io/ios/app/brightpocket-compliment-log/id1521773296)
- [QuickInbox: Fast Notes](https://appshunter.io/ios/app/quickinbox-fast-notes/id1521985749)
- [OneView: Expiring Secret](https://appshunter.io/ios/app/oneview-expiring-secret/id1523017286)
- [RandomPick: Wheel & Teams](https://appshunter.io/ios/app/randompick-wheel-and-teams/id1524590153)

All apps by Jinwan Kim: https://appshunter.io/developer/1446513824

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-10-09.*