I tried running sheltered from the f-droid repository with it not really working that well; refusing to show notifications during setup. I'm not sure of this is because it hasn't been updated in the last 12 months, or if its something on my end.
Any help is appreciated.
Insular seems similar to shelter, also on f-droid.
I have used Insular for the last 12 months and it's unobtrusive and effective.
what are the differences between Insular and Shelter?
No idea. I have never used Shelter.
Used insular before my GrapheneOS phone. Never had an issue.