Help to find the app: block websites (even when tethering)

Hi guys,

I've been looking for such app for weeks now. Basically I want to block some websites (http addresses) on my phone.
It should also work when somebody tries to access these websites when using my phone's internet connection via hotspot (wifi tethering).

Ideally it should be possible to add new websites to block list without password, but to unblock the websites, disable or uninstall the app should be password protected.
I suspect it will only be possible on rooted devices.

I thought maybe one way would be to modify the hosts file. Should work in case of tethering too?
It is quite uncomfortable and I couldn't find one which is password protected and cannot be uninstalled.

Maybe a combination of apps (separate app to password protect the blocking website) could work.

Any ideas?


Thank you guys!