That's a normal message that Play Protect throws up to warn against installing unknown apps from unknown sources, so don't be surprised if you see it. Lastly, since Darker Sky is a newly signed app that hasn't been submitted to the Google Play Store yet (.and it obviously will never be submitted), Google Play Protect may warn against installing it. I'm told the developer is the only one with posting privileges on this channel, though, so new releases won't be coming from any other source.
The developer aims to post updates on this channel but won't be signing their name on new messages so they can remain anonymous.
You can download Darker Sky from the Telegram channel linked below. Lost Skies is a cooperative survival adventure for 16 players set among the clouds, in a vast sky of floating. User ratings for Light Pollution Map - Dark Sky. Humble Games and Bossa Games unveiled their upcoming game Lost Skies. The developer in question is well-known by us for their work on reverse engineering other popular applications, but they decided a low-profile release was more appropriate this time around. Download Light Pollution Map - Dark Sky & Astronomy Tools 5.1.0 APK for Android right now. Darker Sky was made by a prolific developer and reverse engineer who wishes to remain anonymous since this modification was done on shaky grounds.