# Telemetry

Fenix uses Mozilla's telemetry service (Glean) and LeanPlum 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 SDK autogenerated docs](metrics.md).

## Leanplum
See [here](https://github.com/mozilla-mobile/fenix/blob/master/docs/mma.md) for details on Leanplum usage in Firefox Preview.

## Crash reporting
See [here](https://github.com/mozilla-mobile/fenix/blob/master/docs/crash-reporting.md) for details on crash reporting in Firefox Preview.
