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By The University of Michigan

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Learn how to use Entrain at Jetlag is the result of a disrupted circadian clock. Entrain simulates your circadian clock on the phone and makes mathematically optimal lighting recommendations to help you adjust as fast as possible to new timezones and schedules. The recommendations, which tell you when to seek light and/or dark, are based on new search in the journal PLoS Computational Biology. For more information visit

What's New in Version 2.0

- Updated user interface
- New lighting logging system
- Expanded help section
- Expanded jet lag rating system
- Added new cities to time zone list
- Added export option for lighting history

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Customer Reviews

Great concept, poor execution

I just got back from a trip from china and wanted to use this app. I love the fact that it is data driven and shows graphs. I really had trouble telling it I was getting back from a trip and that I spent 18 hours traveling. I like that you can edit your past data, but I couldn't tell it I got home yesterday. Then once I think I got everything entered correctly, it just told me when to seek light and dark, not when to actually sleep or stay awake. I has a lot of issues trying to get this to work. I might have done something wrong, but it still means it is not intuitive to use. I eventually gave up and uninstalled this app, much to my disappointment. It had everything I was looking for, but was just too difficult to use...

Doesn't seem to adjust based on changes to lighting history

The app is more helpful than anything else I've tried when I need to adjust to a new time zone, but in the latest update, it doesn't seem to adjust the lighting recommendations after I change my lighting history. I like the clear indication of the time zone in this update.

"Begin Light" at 1:42 am?

If this is what it takes to "entrain" my body to a new time zone, count me out. In order to reduce my adjustment time from 9 days to 4 days, the app said I should commence a light-dark schedule of "beginning light" in the wee hours of the morning in the days before my trip, and "beginning dark" in the early afternoon. Does anyone actually do this? Do they want me to set an alarm at 2 am, wake up, turn on a light, and fall back asleep? One of the strangest apps I've ever seen.

View In iTunes
  • Free
  • Category: Travel
  • Updated:
  • Version: 2.0
  • Size: 6.1 MB
  • Language: English
  • Seller:

Compatibility: Requires iOS 7.1 or later. Compatible with iPhone, iPad, and iPod touch.

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