logoCaffeine Zone™ 2

Caffeine Zone™ 2 is an iPhone app (over 80,000 downloads) that monitors, predicts, and displays a user's caffeine level in real-time based on a pharmacokinetic model of caffeine and the user's input of when they consume caffeine. It can be used as an educational tool to teach how to use caffeine products wisely and effectively (many probably consume too much caffeine, see here for a humorous anecdotal account that a user pointed out to us). The app was developed by the ACS Lab at the Penn State University (as unfunded work after the grant ended) and spun out using a small company with written permission of ONR and Penn State where we are transitioning this research out of the lab into the hands of users.

Caffeine Zone™ 2 users can enter their caffeine consumption and the app generates a line chart of predicted caffeine level for the next 24 hours. It also shows a cognitive active zone, an area of level where most people will feel active, and sleep zone, an area of caffeine level where most people will be able to sleep. These values are adjustable. These zones can be changed to represent individual differences. There are a lot of individual differences, and including them would be difficult and including their interactions would be impossible.

It runs on the iPhone and the iPod Touch so it is highly portable and easy to use. It runs on the iPad as well. We will be extending it and continue to test it. Comments, discussions, collaborations, and sponsorship are very welcome.

Caffeine Zone 2 Lite (Free with Ads) Caffeine Zone 2 ($0.99 without Ads)

The app is based on research sponsored by ONR but was developed after the grant ended using exclusively non-ONR funds. The results in the app are consistent with the Institute of Medicine/National Research Council's suggestions for use of caffeine in the military [cached copy], and CaffeineZone includes as a menu item the caffeinated gum found in some rations and available in many convenience stores. This caffeinated gum was developed in cooperation with Walter Reed (e.g., here), and has an NSN number, 8925-01-530-1219. Also see an article on SEALS using caffeine, McLellan's article, a Navy report, and a review by Canadian Forces where caffeine has a significant effect. Similar effects of caffeine as an aid for high-tempo operations or extended work hours can be seen in many many non-military situations.



v2.0.1 (current)

Screenshots (from versions 2.0.1)

graph of caffeine in caffeinezonehistory in caffeinezone setting page in caffeinezone

Video a user put onto YouTube, 20feb2012, probably related to this blog, ApfelNet.de, Folge 103: Caffeine Zone 2 Lite [in German, of older version of Caffeine Zone]


System Requirements



Media References to CaffeineZone


Last Updated: 16 sep 2013
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