Tally for Android

The phone half of Tally — a money manager for people whose money is in more than one currency.

Web app: hanifedma/tally

---

---

What it is

The same ledger as the website, not a copy of it. Both apps read and write the same Postgres and both listen to the same realtime stream, so an expense entered here appears in the browser about a second later, and the other way round.

• Kotlin, Jetpack Compose, Material 3
• minSdk 23 — Android 6.0, which is roughly 99% of the phones in use. As low as Tally can go: Credential Manager's Google sign-in needs 23, and below that there is no sign-in to offer.
• Google sign-in through Credential Manager, the current API
• Works with no signal: the ledger is cached on the device and edits are queued
• Works with no account at all — see below
• English and Korean, dark and light — the setting lives on the account, so changing it on a laptop changes it here

Many at once, with an AI

The same feature as the web app's. On the phone, Export as CSV → Claude, ChatGPT or Gemini hands the file and the instructions straight to that app when it is installed — named in the manifest's <queries>, which Android 11 and later need before an app can see another — and otherwise saves the file and opens the website, with the instructions on the clipboard. The 📋 button above the + is where the reply is pasted.

Without an account

Use without an account on the sign-in screen gives you the whole app with nothing to set up and nothing sent anywhere. It is not a demo: it is the same LedgerRepository with local = true, which closes every path to the network and leaves the rules — client-made ids, soft deletes, whole-row writes — exactly as they are. The device cache stops being an optimisation and becomes the ledger.

Nothing is queued in that mode, on purpose. An outbox that could never drain would be the only thing holding a row, and the file it lives in is not the one the app treats as the ledger.

Signing in later offers, once, to copy that ledger into the account. The rows keep their ids; only the derived ones — the starter categories and accounts, whose ids come from the user id so two devices seeding one account write one set of rows — are translated, along with every reference to them. Nothing is erased at the far end, so a failure there loses nothing.

This is also the only way in on a phone with no Google Play Services, where Credential Manager cannot offer an account at all.

Setup

See SETUP.md. It is short, because the real work is in the web repo's SETUP.md — one Supabase project and one Google OAuth client serve both apps.

Building

./gradlew assembleRelease     # app/build/outputs/apk/release/app-release.apk
./gradlew installDebug        # onto a connected device or emulator
./gradlew test                # 82 unit tests, no device needed
./gradlew connectedAndroidTest  # the screen tests; needs a device
./tools/screenshots.sh        # docs/screenshots/; needs a device

tools/screenshots.sh drives device-only mode, so it needs no Supabase project and no Google account. It loads the same demo ledger the web screenshots use — generated by the web repo's tools/demo-cache.mjs — so the phone and the browser are photographed holding exactly the same money.

The screen tests install the debug build, and Android will not put that over a copy signed with the release key: the run stops at INSTALL_FAILED_UPDATE_INCOMPATIBLE before a single test starts. Uninstalling Tally to make room deletes a ledger kept only on that device, so run them somewhere the released app is not — an emulator started with -read-only forgets the whole visit when it closes, which makes it a good place.

Signing is described by a keystore.properties at the repo root, which is not committed — see keystore.properties.example. Without it the release build falls back to the debug key: still installable, still testable, just not something to publish, and Google sign-in will refuse it because the certificate is not the one registered.

Layout

core/       Money, Dates, Calc, Compute, Models, Ids
            — the same arithmetic as the web app's money.js
data/       Supabase, LedgerRepository, LocalStore, Prefs
auth/       AuthManager — Credential Manager → Supabase
i18n/       Strings.kt — GENERATED, do not edit
ui/         theme, TallyViewModel, TallyApp, screens/, components/

Strings.kt is generated

It is produced from the web app's i18n.js:

cd ../tally && node tools/gen-android-strings.mjs ../tally-android

Two hand-maintained copies of nearly three hundred strings drift within a week — a key renamed on one side and the phone quietly starts showing tx.saveAnother where a button should be. So the web table is the source and this is a build artefact that happens to be committed.

The handful of strings only the phone says — one names a file that exists only in this repo, one names a failure only Credential Manager can have — live at the top of the generator, not pencilled into Strings.kt afterwards, where the next run would silently delete them.

Nothing checks this file against i18n.js automatically: that table is JavaScript and these tests run on the JVM. ParityTest checks what it can from this side — that every key exists in both languages, and that no {placeholder} was lost in translation. Falling behind i18n.js is caught by running the generator, not by a test.

The parity tests

app/src/test/.../ParityTest.kt is not a test that Kotlin does what Kotlin does. Every expected value in it was produced by running the web app's money.js in Node and pasting the answer in. It asserts that the phone and the browser put the same number on the screen for the same row — the same formatted string, the same converted amount, the same derived UUID. If one side drifts, it fails.

Why the release build is not minified

Ktor and kotlinx.serialization — the two libraries the whole sync layer rests on — resolve types reflectively at the edges, and a wrong keep rule fails at runtime on a user's phone rather than at build time here. A few extra megabytes is the right trade for a sync layer that cannot silently work in debug and break in release.

A limitation worth knowing

Google sign-in needs Google Play Services. On a phone that has none — some Huawei models, some custom ROMs — there is no way in, and Tally will say so rather than showing a button that cannot work. The web app works on any of them.