Join the pilot program here

Thank you in advance for contributing to this research project!


iPhone App installation -- and Testflight

We don't need to use TestFlight anymore! Get MCF from the normal place -- the App Store.

If you originally installed MCF via TestFlight, DO NOT UNINSTALL THE APP! You will lose the on-phone app data.
Instead, go to the App Store and GET/INSTALL the MCF app, which will simply UPDATE the app and keep your data.

How much cellular data will the app use?

The app will upload less than 3 megabytes per day while it is running in the background, if you are traveling for 2-3 hours in a day. If you move around all day, it could use up to 20 megabytes. Cellular data use cannot be disabled in the app, because we need to continuously update the carbon footprinting calculations.

When you are viewing your Pathway Diary or carbon footprint feedback, the app will use more data (but not much more), just like any other app that receives updates over the internet.

How much battery will the app use?

The app runs periodically in the background only when the phone is moving, to collect the minimum amount of data needed for calculating footprints. For most smartphones, it will use less than 10% of the battery each day, if you are moving around for about 3 hours per day (20 to 30mAh per hour when the phone is moving).

If you are viewing the app on the phone's screen, it will require as much battery as any other app in active use.

Android Users: If you normally don't turn on GPS/Location Services, the battery usage might appear high. This is because lots of other apps will also start requesting the phone's location, which drains the battery in addition to using the GPS itself. Shutting off location permissions for those other apps AND for specific Google features will help reduce battery use substantially. For Android 8.1:

  • Settings -> Security & Location -> Click on LOCATION in the Privacy Section
  • At the bottom of this screen, click Google Location History, toggle it off so that Google isn't tracking all the time
  • This screen also shows recent location requests, e.g. Google is always there.
  • In the same Location screen, click on App-Level Permissions (or Settings -> Apps & Notifications -> App Permissions -> Location)
  • Toggle off anything that you don't want to request your location (especially Google), except for Google Play Services and Mobile Carbon Footprinting

I am concerned about sharing my location/GPS data.

We are following protocols to protect your privacy and personally identifiable information, and we have submitted these protocols to MIT's COUHES. We hope that learning about your carbon footprint - and contributing to this research - will make the experience worthwhile.

Only your Display Name and simplified carbon footprint summaries will be visible to other participants. Trained investigators will only use your contact info to contact you directly about pilot project updates and to share automatically generated reports on your progress through the pilot project steps. Only one researcher (J. Cressica Brazier) has access to the data stored on the secure server, and she will never look at the GPS/pathway data directly - only you can see your pathway diary, using your phone. Your data will be anonymized and aggregated before sharing with other project investigators and research publications.


The app is crashing every time I try to open it!

This happens sometimes when the app version updates. On Android, go to Settings -> Apps -> MCF -> Storage -> Clear Data. The app should start up and allow you to log in again. In the current version, your confirmed daily pathway data (colored blue) will no longer be on the phone (don't worry, it is stored on the server!), but I will be able to restore these data in the next app version.

The menu button stopped working!

You should still be able to swipe from the left to open the menu. The menu button might work again when a new version of the app is installed, or if you reinstall the app.

It is so slow! The buttons are so small!

Yes indeed. It is handmade for research goals, so thank you for being patient with it!