Send usage data on Firefox mobile browsers

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  • Revision id: 142570
  • Created:
  • Creator: Joni
  • Comment: updated with leanplum with legal review
  • Reviewed: Yes
  • Reviewed:
  • Reviewed by: jsavage
  • Is approved? Yes
  • Is current revision? No
  • Ready for localization: Yes
  • Readied for localization:
  • Readied for localization by: jsavage
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Controls in the settings menu allow you to turn off data collection from Firefox on your mobile devices. Here is what those control actually turns off:

  • Firefox for Android, Firefox for iOS, and Firefox Focus collect data about installations and retention using a third-party tracking framework called Adjust and Leanplum. This helps Mozilla determine the origin of the installation by answering the question, "Did this user on this device install the application in response to a specific advertising campaign performed by Mozilla?"
The Adjust framework consists of a open source software development kit (SDK) built into Firefox and a data-collecting Internet service backend run by the German company adjust GmbH.
  • On iOS, Firefox uses a mobile marketing vendor called Leanplum. See their privacy policy here. This data allows us to test different features and experiences, as well as provide customized messages and recommendations for improving your experience with Firefox.
  • Firefox Focus also uses Mozilla’s telemetry system to measure basic interactions with the browser, such as the number of times you hit the erase button, select a search hint, or open a page in another browser. You can read more about this data collection here.
  • Firefox Klar does not utilize Adjust. Mozilla’s telemetry system is turned off by default on Klar. You can turn telemetry on in the Klar Settings menu if you want to help us collect data to better understand and improve our product.

What data is collected and sent to the adjust backend?

For a new install, the application sends an anonymous "attribution" request to the adjust servers. This request describes how the application was downloaded, for example, whether it was downloaded directly via the App Store or through a marketing campaign link. The data includes an advertising ID, IP address, timestamp, country, language/locale, operating system and app version.

Firefox for Android, Firefox for iOS, and Firefox Focus will also occasionally send anonymous summaries about how often the application has been used. These summaries only include information regarding whether the app has been in active use recently and when.

Additionally, Firefox Focus will report what features of the application are being used. It will send an anonymous report containing the specific filters being selected and count how many times the search, browse and erase button is pressed. This is described in more technical detail in Install and event tracking with the Adjust SDK

You can turn off this collection and reporting in the Settings menu:
  • Firefox for iOS: Tap the menu button at the bottom of the screen, followed by the Settings icon. (You might need to swipe to the left first). Turn the switch off next to Send Anonymous Usage Data.
  • Firefox for Android: Tap the menu button (either below the screen on some devices or at the top-right corner of the browser) followed by Settings (you may need to tap More first) . Tap on the Privacy section and remove the check mark next to Firefox Health Report.
  • Firefox Focus & Firefox Klar: Tap the settings button at the top right of the screen. If you are in the browser you may have to hit the Erase button first. Turn the switch off next to Send Anonymous Usage Data.

Frequently asked questions

Why is data sent to a third-party?

Mozilla has high privacy standards and expects the same of vendors that provide us with services. We use a mobile analytics solution called Adjust. We selected Adjust because they are the best analytics solution for Firefox and because they maintain strong protections for users. Adjust also holds ePrivacy certification and complies with strict German privacy laws. Equally important, Adjust SDK is open source. This provides greater transparency for anyone that wants to understand exactly what data Adjust collects. The information that we send to Adjust is described here.

Do Firefox browsers track what sites users have visited?

Users’ browsing history on Firefox never leaves the devices and is not sent to Mozilla or our mobile analytics vendor Adjust. Like most web browsers, Firefox keeps a local copy of your browsing history on the device during a browsing session. This is true for nearly all browsers and enables functions such as changing colors of links that have already been clicked. Firefox makes it easy to remove your browsing history from your device with a single tap on the Erase button located in the top right corner of each Focus browser window.

Does Mozilla collect personally identifiable information from Firefox?

Neither Mozilla, nor our mobile analytics vendor Adjust, receive personal information from Firefox users. For example, we do not receive usernames, email addresses, or URLS from Firefox users.

What is the advertising ID and what is it used for?

The Adjust SDK integrated into Firefox utilizes Apple’s IDFA - “ID for Advertisers.” This is an identifier that Apple makes available to advertisers for iOS devices. Apple assigns and manages the IDFA for each device, and allows iOS users to turn-off their IDFA or periodically reset it (resetting the IDFA reduces the ability of advertisers to track users).

Our mobile analytics vendor Adjust uses this IDFA to attribute a Firefox app installation to a previously served advertisement for Firefox. In other words, Adjust determines if iOS users discovered Firefox by clicking on a mobile advertisement to install the Firefox app, and then can provide aggregate numbers of app installations to Mozilla. We think Firefox is a great privacy product and we want people to know about it. Adjust helps us know that our message about Firefox is effective.

Mozilla does not have access to this IDFA, nor do we receive information about the IDFA in the aggregated activity summary reports we receive from Adjust. If the user enables “Limit Ad Tracking” in the the iOS Privacy Settings, then the IDFA is also not used in any communication with Adjust.

Why does Firefox enable data collection by default?

The Firefox for mobile browsers are new products. With all new products we seek to establish market fit validation as quickly as possible. We decided to take an opt-out approach to gain insight from a more diverse group of users about their first interactions with the product. We believe such approach helps us gather usage information that is as unbiased as possible in order to really understand how Firefox browsers are being used and consequently how it can be improved.