I wanted to send a first test message through MobilePush to my registered device (Android), but the contact's activity dashboard just says "Status: Error" without any further explanation. Is there a possibility to get more details on why it failed?
Check the docs for Push Configuration Troubleshooting:
One of the most common problems is customers creating their app in the App Center with the
Android Key rather than the
Server Key, but using a REST client like PAW and trying to send directly to the device will help isolate your problem.
There might be a misconfiguration in how your device is registering with SFMC. Check the app id, access token and gcm sender id for their accuracy.