# FAQ

**Contents:** [Safety](#safety) · [Your apps](#your-apps) · [Day to day](#day-to-day) ·
[Other TVs](#other-tvs) · [The project](#the-project)

## Safety

**Is this legal?**
Yes. You are changing settings and app states on a TV you own, through the debug
interface the manufacturer ships. Nothing bypasses a licence check, and no Amazon
code is modified or redistributed.

**Can this brick my TV?**
The scripts never write to `/system`, never remount it, never touch the bootloader,
and refuse to disable anything on `data/fireos/never-disable.txt`: the home screen,
settings, inputs, the tuner, remote pairing and Prime Video. The realistic worst
case is a TV that boots to Amazon's home screen, which `./scripts/restore.sh` or
`./scripts/launcher.sh` fixes.

**Does it need root?**
No. Everything runs as the `shell` user that ADB debugging gives you.

**How do I undo it?**
`./scripts/restore.sh`. It turns every package back on, clears the app-ops and
network rules, puts back the settings your TV had before (saved by
`preflight.sh`), switches the DNS filter off and returns HOME to Amazon. Apps you
asked to have uninstalled come back from the Appstore.

**Does the project itself phone home?**
No. On your computer the scripts download the personalDNSfilter app from F-Droid,
dumbtv home from this repository's releases (checked against a pinned SHA-256),
and the HaGeZi tracker list; SmartTube too, if you ask for it. Nothing is
uploaded. The launcher has no internet permission.

## Your apps

**Will it remove an app I watch?**
No. Amazon's ads, trackers and telemetry are disabled; apps are not touched. An app
is only removed when you name it, in `configure.sh` or with
`./scripts/configure.sh --remove <package>`.

**Will Prime Video work?**
Yes, by default. Prime Video needs its video CDN and Amazon's push service, and
both stay reachable unless you answer no to Prime in `configure.sh` (`PRIME=0`).

**Will YouTube work?**
Yes. The filter never blocks Google or YouTube, and `verify.sh` checks that. The
YouTube app is only replaced if you ask for SmartTube; see
[YOUTUBE.md](YOUTUBE.md) for why YouTube's own ads cannot be blocked by DNS.

**Will the voice remote work?**
Yes, by default: Alexa is kept. If you answer no to Alexa in `configure.sh`
(`ALEXA=0`), Alexa and the app that owns the microphone are switched off and their
servers blocked; the buttons and pairing keep working. To bring it back:

```sh
./scripts/configure.sh --alexa 1   # then run ./scripts/restore.sh and ./scripts/all.sh
```

**Will the Appstore work?**
Yes. Its hosts are never blocked.

## Day to day

**Does it survive a reboot?**
Yes. Disabled packages, the filter and the home screen all come back on their own.

**Does it survive an Amazon update?**
Updates do not arrive while the DNS filter runs: it blocks the update servers. If
an update does land, it can re-enable packages and reset settings; run
`./scripts/all.sh` again. To update on purpose, run `./scripts/restore.sh`, let
the TV update, then `./scripts/all.sh`.

**Does it survive a factory reset?**
No. A factory reset undoes everything, including this. Run the scripts again.

**Do I need a computer every time?**
Only to run the scripts. After that the TV works on its own.

**Wi-Fi or USB?**
Wi-Fi: `adb connect <tv-ip>:5555`.

**Pressing HOME shows Amazon's home for a few seconds.**
It should land on dumbtv home in about a quarter of a second. Run
`./scripts/launcher.sh -y`; see [TROUBLESHOOTING.md](TROUBLESHOOTING.md).

## Other TVs

**Is this only for Fire TV?**
The scripts are for Fire OS: Fire TV sticks, cubes and Fire TV Edition
televisions. Android TV and Google TV can be cleaned the same way by hand, and the
catalog has reports from people who did. Samsung, LG, Roku, VIDAA, Vizio,
Panasonic and Philips Saphi give an owner no shell. [OTHER-TVS.md](OTHER-TVS.md)
has the detail for each.

**Can I install a different operating system?**
No. Every current TV has a signed boot chain and a verified system partition.
[WHY-NOT-REPLACE-OS.md](WHY-NOT-REPLACE-OS.md) explains why.

**Why not just use a Pi-hole?**
If your router lets you set DNS, a network blocker is a good choice. dumbtv's
filter runs on the TV itself, so it works on any network, and it is paired with
the rest of the cleanup: the packages, the settings and the home screen.

## The project

**Why its own launcher?**
A home screen needs no internet access, no advertising ID and no permission to
install apps. dumbtv home is 54 KB, open source and asks for no permissions on
Fire OS 7 and 8. Check it yourself: `aapt2 dump permissions dumbtv-home.apk`
lists three, each limited to Android 8.1 and earlier, which only Fire OS 6's Keeper
uses.

**Who made this?**
[Muzzammil](https://x.com/DevMuzzammil), with people who ran it on their own TVs
and sent fixes and device reports. They are credited in the
[README](../README.md#thanks).