Re: Smart TVs?
"I use a no root firewall to prevent the tablet/phone from connecting to certain sites/addresses."
System apps can work below such firewalls (much as Windows 10 does by an internal lookup), and the only way to add a system-level firewall that can actually deal with them is to root your phone, which has its own strings attached (such as disabling root- and custom-aware apps, and Android has gotten stricter and stricter with enforcing this).
And the thing with Whispernets is that they don't touch any network you own; they're their own networks outside your control.