I’ve noticed this issue with really early versions of UE4 all the way to 4.11 -
Appears on Android devices using the default sky. The Sun disc seems to have
issues with aliasing. Moving the camera causes it to ‘spaz out’ incredibly.
Never been able to fix it, but definitely a replicate-able issue.
Thanks for the report. I’ve entered a ticket in our bug tracking database to take a look at this.
I have a feeling it’s just an issue with limited precision available on mobile hardware and the way the sample content has been made, but if that’s the case we should fix the sample content.