Nothing updates this app on its own. It is downloaded as an APK from a web
page, so there is no store to notice a release and no background updater to
install one — a person can run a build from months ago indefinitely, through
every fix that came after it, and never find out. That is the part of
sideloading that is genuinely worse than a store, and this is the only thing
that closes it.
The background check asks the RELAY the install is signed in to, not a fixed
address of ours. Pointing every install at flamenetmessenger.com would mean an
app whose whole claim is that it does not phone home checking in with us on a
timer, from every device, including the self-hosted ones that deliberately
never contact us at all. A relay that publishes no manifest simply produces no
prompt.
"Check for updates" in Account is the other half, and the reason the fallback
to our site exists: pressing it is a question the user asked, so answering
"your relay does not publish updates" when we plainly could is unhelpful. It
tries the relay first and names whichever host answered, so it is never a
silent phone-home. It also distinguishes "no newer build" from "could not
check" — reporting silence as good news is how somebody sits on a build with a
fix in it believing otherwise.
The download URL is built from the host that answered and never read from the
manifest. A `url` field would let any relay send its users to an APK on a host
of its choosing; Android's signature check is a backstop, not a reason to build
the hole in front of it. A test asserts a hostile manifest cannot move it, and
fails if the guard is removed.
versionCode is bumped and `scripts/release-manifest.sh` reads it back out of
the built APK, so the manifest and the artifact cannot drift.
⚠️ Nobody already installed sees this: every build before this one has no
check in it, so the first prompt anybody gets is for the build after this one.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
