Valet is a fork of Simple Bitcoin Wallet (aka SBW).

As formerly the original, it uses an IMMORTAN library that allows extensive Lightning Network support in addition to non-custodial Bitcoin wallet features in Android.

As much as SBW, it is fully autonomous and does not rely on any kind of centralized service (such as Google services, routing servers, special LSP nodes etc). The destinctive feature of Valet as opposed to the original SBW is Fiat Channels support that replaces original Hosted Channels solution and allows users to have "Hosted" Channels capacities tied to value of some other assets for example US Dollar or Euro. This is technically achieved by assigning a special "ticker" to each channel and adding satoshis-denominated "rate" into fiat channel state (more...).

Or download the latest APK from the Releases Section.

Valet project Roadmap.

Building from source

git clone https://github.com/standardsats/valet.git
cd valet
podman build -t valet .
podman run -v $PWD:/app/valet:z valet

The container runs ./gradlew assembleRelease && ./gradlew bundleRelease, producing an APK for every product flavor (mainnet, tnet3, tnet4, regtest) under app/build/outputs/apk/<flavor>/release/, named <applicationId>_<versionCode>.apk (e.g. finance.valet_111.apk for mainnet), plus .aab bundles under app/build/outputs/bundle/release/.

Released APKs have to be reproducible byte for byte, because F-Droid rebuilds them and refuses to publish a release it cannot reproduce. Read REPRODUCIBLE_BUILDS.md before changing anything about how the APK is packaged or signed.

Signing APKs with your self-signed certificate

Gradle handles zipalign and APK signing automatically when the right environment variables are present at build time, so for APKs you usually don't need to run zipalign/apksigner yourself.

1. Create a keystore (once):

   keytool -genkey -v -keystore release.keystore -alias release \
       -keyalg RSA -keysize 2048 -validity 10000
   

2. Pass the signing credentials into the build container:

   podman run -v $PWD:/app/valet:z \
       -e SIGNING_STORE_FILENAME=/app/valet/release.keystore \
       -e SIGNING_KEY_ALIAS=release \
       -e SIGNING_STORE_PASSWORD=<keystore/key password> \
       valet
   

   With these variables set, every assemble<Flavor>Release task is finalized by a sign<Flavor>ReleaseApk task that zipaligns and signs the APK in place (--v1-signing-enabled true --v2-signing-enabled true), followed by a verify<Flavor>ReleaseApk task that checks the result is still reproducible. If SIGNING_KEY_ALIAS is not set, the build still normalizes timestamps and zipaligns the APK, but leaves it unsigned.

Manually signing an unsigned APK

Don't, if the APK is going to be published. F-Droid rebuilds each release and grafts the published signature onto its own build; that only works if signing left the ZIP layout untouched, and apksigner rewrites the alignment padding of every uncompressed entry unless it is told not to. The build's signing task passes the flag that prevents this and then proves it worked — a hand-rolled apksigner sign does neither.

If you are signing a throwaway build for a device, the invocation the build uses is:

$ <Android SDK dir>/build-tools/36.0.0/apksigner sign \
    --alignment-preserved true \
    --ks release.keystore --ks-key-alias release \
    --v1-signing-enabled true --v2-signing-enabled true \
    app/build/outputs/apk/mainnet/release/finance.valet_111.apk

The APK must already be zipaligned, which assemble<Flavor>Release does. Do not run zipalign on it again afterwards. See REPRODUCIBLE_BUILDS.md.

Signing App Bundles (.aab)

bundleRelease is not covered by the Gradle signing task above, so any app-release.aab produced under app/build/outputs/bundle/release/ is always unsigned. To sign one for personal use:

$ <Android SDK dir>/build-tools/<version>/zipalign -v 4 \
    app/build/outputs/bundle/release/app-release.aab \
    app/build/outputs/bundle/release/app-release-aligned.aab

$ <Android SDK dir>/build-tools/<version>/apksigner sign \
    --ks release.keystore --ks-key-alias release \
    --v1-signing-enabled true --v2-signing-enabled true \
    --min-sdk-version 30 \
    app/build/outputs/bundle/release/app-release-aligned.aab

Installing on a device

adb devices
adb -d install -r app/build/outputs/apk/release/finance.valet_107.apk

(uninstall a previous build first with adb -d uninstall finance.valet if you hit a signature mismatch).

Optional: detached PGP signature for distribution

If you plan to share a signed APK, you can additionally attach a detached PGP signature and checksum:

APK=app/build/outputs/apk/release/finance.valet_107.apk
gpg --batch --yes --local-user <your GPG key id> --armor --detach-sign \
    --output "${APK}.asc" "${APK}"
sha256sum "${APK}" "${APK}.asc" > "${APK}.sha256"
gpg --armor --export <your GPG key id> > pubkey.asc

Verification with apksigner

apksigner verify --print-certs --verbose finance.valet_107.apk

Output should contain the following info:

Verifies
Verified using v1 scheme (JAR signing): true
Verified using v2 scheme (APK Signature Scheme v2): true
Number of signers: 1
Signer #1 certificate DN: CN=Bitcoins wallet developer
Signer #1 certificate SHA-256 digest: dca2c3527ec7f7c0e38c0353278e7a5674cfa6e4b7556510ff05f60073ca338a
Signer #1 certificate SHA-1 digest: 14659e7de5a71f2608bf4a889c0f8d043147e203
Signer #1 certificate MD5 digest: e3102232a4754705c8917710765b9635
Signer #1 key algorithm: RSA
Signer #1 key size (bits): 2048
Signer #1 public key SHA-256 digest: dc97f0f2e34167015914600d8fa748f908d578bcedb79664d010de3c9bdebf13
Signer #1 public key SHA-1 digest: c4400469d5ad807dd9394785f1fa95003588a091
Signer #1 public key MD5 digest: e4e1f847e0cb0a9703dc4f9323fd6d87

Acknowledgements

Original SBW Project couldn't be done without LNBig support and A. Kumaigorodski development efforts.

Donate

There is permanent campaign going on Geyser and Tourniquet for supporting maintenance and development of this project.