# Telemetry Fenix uses Mozilla's telemetry service (Glean) to measure feature performance and engagement. ## Glean pings and metrics By using the Glean SDK, Fenix can send the pings the SDK owns and defines, as documented [in the Glean SDK docs](https://mozilla.github.io/glean/book/user/pings/index.html). Additional metrics or pings defined by Fenix are documented in the [Glean Dictionary](https://dictionary.telemetry.mozilla.org/apps/fenix). ## Crash reporting See [here](https://github.com/mozilla-mobile/fenix/blob/main/docs/crash-reporting.md) for details on crash reporting in Firefox for Android.