Two separate reasons updates were impossible, both fixed here. **Every CI build was signed with a different key** (issue #2803, measured with `apksigner --print-certs` across two runs). No signing config meant AGP's debug keystore, which AGP GENERATES when absent — and every job starts from a fresh container. So no build could ever be installed over another: the only way through was uninstall-then-install, which deletes the app's database and every local note with it. **versionCode was hardcoded to 1.** `build.gradle.kts` has read a `THOUGHTSYNC_VERSION_CODE` property since the skeleton landed; nothing ever passed it. Even with signing fixed, every APK would have claimed to be the same version and nothing could tell a newer one existed. It now comes from `GITHUB_RUN_NUMBER` — the same monotonic counter the desktop's version scheme already uses, needing no state between runs and immune to the shallow checkout that makes a commit count useless here. The version NAME comes from the desktop's `build-version.sh`, so both surfaces report one product version rather than two that can disagree. **The alias is hardcoded, not a secret.** It is fixed for the life of the app and already written into the certificate every install carries; hiding it would buy nothing and stop this file describing its own signing. Two secrets, not three — and PKCS12 cannot hold a key password distinct from the store password anyway, so `keyPassword` is the same value by necessity rather than by shortcut. **The lane now builds RELEASE when it can sign, debug when it cannot.** That is not cosmetic. A debug APK is `debuggable`, which on a phone holding personal notes and a device sync token means anyone with adb can read both. Which meant confronting something the release path would have shipped quietly: `cargoNdkDebug` was hardcoded to the debug Cargo profile and every variant took its `.so` from it, so `assembleRelease` would have packaged an UNOPTIMISED store and sync engine. Now one `cargoNdk` task takes its profile from a property, and the whole run uses one profile. A debug/release task pair would have been the tidier shape and would have made a run that both type-checks and packages pay the four-minute cross-compile twice — this runner has no working Gradle or Cargo cache, so that cost is real on every push. The run prints the signing certificate after assembling, so the fingerprint can be compared against the one recorded at generation. Signing with the wrong key produces a perfectly valid APK that simply refuses to install — a failure that otherwise surfaces on the device, long after the run is green. `.gitignore` learns `*.jks`, `*.keystore`, `*.p12`, `*.b64` first, so generating a keystore anywhere near this tree cannot go wrong. Also corrects the record: the comment this replaces cited "Scribe task 2136" as though it were a standing rule. It is not one — none of the 46 always-on rules mentions signing keys. 2136 is a desktop-updater task whose REASONING got repeated until it sounded like policy. The reasoning holds, and holds harder on Android where a key cannot be rotated without the original, so the practice is unchanged; the citation is now honest about what it is.