Warn User if Battery Saver mode in Enabled
As mentioned in your support article, Battery Saver mode causes problems on Android phones - https://support.strava.com/hc/en-us/articles/216918967. This got me today, and of course it was my fault, however Android does provide an API to check if Battery Saver mode is enabled, and then gives you the ability to monitor it for changes.
It would be nice if when you go to record an activity, before pressing start you get a pop-up notifying you that you are in Battery Saver mode, and then provide the steps necessary to disable it. Those steps can probably just be copy pasted from the article above.