The Noise and the Signal -  Metrics, Monitoring and Alarming at Soundwave

Soundwave is a music discovery app with around 1.5 million installs spread across most countries, and therefore most time zones.

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We use the excellent DataDog, complemented by Cloudwatch,Crashlytics and some internal tools to ensure first and foremost that we know as much as possible about all of our applications and services. 

User Experience Metrics 

In building anything, start from the user and work backwards. The single most valuable category of metrics are those that describe the experience your users are having right now. If the landing page of your app takes 5 seconds to respond, your app is dead. Nothing else matters.  

https://medium.com/soundwave-stories/the-noise-and-the-signal-metrics-monitoring-and-alarming-at-soundwave-c544d2527e75