Love TrackerControl from FDroid. You can fine tune access/block of each app based on classification of network destination (analytics, tracking, necessary, ..)
Love it. Have an "always-on" raspberry pi with usb drive just running syncthing in my home network. That way, I don't have my data "in the cloud" somewhere, I don't have to open my home network for external access to my NAS etc, and always have an up to date "source" when I start syncthing on a tablet or mobile (where i dont have them running all the time).