You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
Felix Krause 7dbbedbf35
Merge pull request #5 from skywinder/master
5 years ago
assets update QR code. Close #4 5 years ago
LICENSE Initial commit 5 years ago Update link to demo 5 years ago
index.html Added QR code when on desktop 5 years ago


What's the user doing

Twitter: @KrauseFx License

Modern web browsers give the user more control over what data they're sharing with websites, for example location services and access to the camera.

However I recently noticed a gap of how websites can determine the activity of the user based on the acceleration and gyro sensor built into modern smartphones, including the iPhone and Android phones.

Using that data, any website can determine if the user is using their phone while

  • sitting
  • standing
  • walking
  • running
  • driving
  • taking a picture
  • lying in bed
  • laying the phone on a table

and probably more, including guesses if the user is actively using their phone at this moment, or even if they're impaired by alcohol.

This project

This was a 1h Sunday night hack project, where I wanted to see how easy it is to guess what the user is doing based on the data, without using any JS libraries, artificial intelligence or even any kind of pattern recognition.

Open the web-app on your mobile device

All source code can be found in a single file: index.html


Take action

This project was by no means designed to be used to track the user, but instead make people aware of how easy it is to use that data, and get Apple to add a permission prompt of acceleration sensors for websites and mobile apps.

You can dupe the radar rdar://34234813 👍

Evil companies can afford to spend more resources on writing an excellent detection algorithm to (ab)use the sensor data to detect what the user is doing without getting their permission.

On the other hand, this could be used for positive things also, imagine a (web)app not showing a certain popup because it notices that you're busy driving a car or walking on a street.


This project is licensed under the terms of the MIT license. See the LICENSE file.

This project is in no way affiliated with Apple Inc or Google Inc. This project is open source under the MIT license, which means you have full access to the source code and can modify it to fit your own needs.