The fleet card reads last-seen from the claw, and only a landed report moves it. Periodic work is deferred while the device idles — Doze stretches the fifteen-minute floor to hours — so a phone sitting in the human's hand could show itself as "last seen 3h ago" with nothing wrong on the claw. Kick a status run on resume, the same way the commands worker already is, and reload the fleet whenever a run lands. The landed-run signal is a new clock in StatusRepository, written in the same edit that saves the snapshot (which only happens once every post of the run succeeded), so the card reloads on a report that actually reached the claw.
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Rhema Android
The phone client of the claw (the resident agent daemon): Kotlin + Jetpack Compose, single module, deliberately small. It chats with the agent, reports phone status as events, shows the agent's notifications as system notifications, executes the agent's phone commands (DND, alerts), and manages the device fleet the claw keeps.
What it does
-
Settings: a nav of submenus mirroring the web UI's settings sidebar — the "Phone" group (Status reporting, Devices) and the "Claw" group (Model providers, Connection), one page per entry behind a back arrow. First launch is the exception: it lands straight on the connection page until a base URL is saved and validated with
GET /healthz. Stores the claw base URL and bearer token (plus a generated, persistent device ID) in app-private DataStore. The Devices page is the Phones card, Status reporting and Model providers their own pages (both described below): the backend instances (GET /v1/providers), each one's live model listing, and the active pair staged as a draft behind an explicit save (PUT /v1/providers/active; it applies from the claw's next turn). Trade-off: the token is stored in plain DataStore rather than EncryptedSharedPreferences;androidx.security:security-cryptois an alpha-quality, unmaintained artifact, and the OS app sandbox already covers the realistic threat (other apps). Backups that could exfiltrate the file are disabled in the manifest (allowBackup=false,dataExtractionRules,fullBackupContent). -
Chat: session list (
GET /v1/sessions, interactive sessions first, the phone's ownphone:*status keys hidden) and one chat screen per session. The applied events persist in a per-session cache (DataStore, newest 500 with the full count as the cursor), so a screen opens on its cached transcript at once and the stream connects with?since=<count>to receive only what is new instead of replaying the whole history; the cache flushes at everyturn_doneand when the screen closes. While a chat screen is open the app holds one SSE connection (GET /v1/sessions/{key}/events, OkHttp streaming GET with the auth header, hand-parsed frames: blank-line delimiteddata:lines,:comment keep-alives skipped, unknown event types skipped). The reader's own messages render as right-anchored bubbles (elevated surface, accent bar on the trailing edge); the agent's turns keep the avatar on the left. The composer POSTs{"text"}; the claw's documented dance is preserved: subscribe first, then POST, the reply arrives on the stream. Thinking deltas render dim and collapsible, tool rows show name/summary with error coloring (bash-like tools render as shell lines instead: dim$prefix, the command line, and an exit-code badge), pasted payloads embedded in a message as pairedU+FFFCmarks render as compact▣N 5Lchips, andattachmentevents render as cards: file name, size, caption, an inline preview for small (≤ 2 MB) images, and a download-and-open row (bytes fromGET /v1/attachments/{id}land in the app cache and open through a FileProviderACTION_VIEW, the only way another app can read a private cache file). The agent'sconsent_requestquestions (a secret, or an approval of a phone control action) render as cards answered in place —POST/DELETE /v1/consents/{id}— andconsent_resolvedsettles them (a reconnect's replay rebuilds the settled states). The streaming reply is finalized byturn_done. The chat renders the claw's presentation identity (GET /v1/agent, cached in DataStore, refreshed per app open and on the session list's refresh): the avatar image when one is set (GET /v1/agent/avatar), else the initials, the name's first letter, or R; the agent's name labels every turn, falling back to "rhema". Replies render as markdown (com.mikepenz:multiplatform-markdown-renderer, GFM flavour: raw HTML stays literal, so model output never mounts as markup; the streaming cursor rides the source text). The transcript is a reversed LazyColumn: the newest turn anchors to the bottom edge, so streamed blocks stay on screen and a reader scrolled into history is not yanked back. -
Phone status source: a WorkManager periodic worker (15 min, the OS floor,
NetworkType.CONNECTED) reads every sensor into one snapshot and POSTs only transitions vs the last successfully-posted snapshot (persisted in DataStore) toPOST /v1/ingest. Each sensor has its own transition rule, tuned to what would otherwise spam:Topic Posts when Needs batterycharging flip, or decile bucket change ( level/10)nothing networkwifi/metered/offlinechangesnothing dndon/off changes nothing locationmoved 300 m or more since the last posted fix location permission appthe foreground package changes usage access grant devicethe identity fingerprint changes (basically once, and on app or OS updates) nothing wifithe connected SSID changes location permission alarmthe next alarm moves nothing heartbeatalways, when a run produced no other post nothing A sensor that is ungranted or unreadable produces no posts for its topic, never an error. Rich readings carry their own honesty: a location payload includes accuracy and fix age, the app payload the package, its label and how long it has been current. The location read requests a fresh fix (fused on API 31+, else gps then network) with a 20 s ceiling and falls back to the newest last-known fix under 30 min; a plain last-known read would answer with whatever another app left cached, which on a stationary phone is where the phone was, not where it is. The heartbeat exists for the fleet's last-seen time: the claw stamps a device "seen" on whatever post lands, so a run with no transitions posts one anyway and the row stays fresh at the worker's cadence instead of the last flip. A failed post ends the run anyway — the snapshot is only saved when every post landed, so the next scheduled run re-derives the whole transition set;
retry()would hand the cadence to WorkManager's exponential backoff (hours) and the phone would read as gone. And because idle devices defer periodic work (Doze stretches the fifteen-minute floor to hours), the app kicks a status run on every foreground: a phone in hand reports then and there, and the fleet card reloads on each landed run (lastReportAt) so its own row reads from the new clock instead of the one it was opened at.Every report is an observation on the claw: it lands in the phone tables (the ingest answers
{"ingested": "observed"}) and aphonetool status question reads it. No report dispatches a turn, so a commute or a session of app-hopping is never a model call per move, and a battery flip never becomes a push notification.Charging flips additionally kick a one-shot worker from a process-lifetime broadcast receiver (
ACTION_POWER_CONNECTED|DISCONNECTED,ACTION_BATTERY_CHANGED). Manifest registration for those actions is refused by the OS (implicit broadcasts, API 26+), so the receiver is registered dynamically in the Application and stays dumb: it only enqueues work. -
Phone fleet: the Settings screen's Phones card is the management surface over the claw's registry (
GET /v1/phones), not a private view: every device the claw has heard from, its self-reported label (thedevicetopic's manufacturer and model), its last-seen time, and a one-line state. This install's row is marked; every other row carries Forget, whichDELETEs the device's records on the claw after a confirm dialog. A device id lives for one install, so a reinstall or a cleared app data leaves the old identity behind as a stale row with an old last-seen time; that row is what Forget is for. A forgotten phone that still reports re-registers on its next run. The Status reporting card names what this phone cannot send until a grant is flipped (location permission, usage access, DND access) and walks to the system toggles; the rows re-read on every ON_RESUME. -
Phone commands: a third periodic worker polls
GET /v1/phone/commands?device=<id>— the agent's consented control queue — every 15 minutes like the other workers (that interval is the control latency; opening the app kicks a one-shot KEEP-coalesced run, so the queue is fresh while the phone is in hand). Commands execute in order, each answered withPOST /v1/phone/commands/{id}/result, which doubles as the ack: a failed post leaves the command queued and the next run repeats it.dnd_on/dnd_offset the interruption filter; they need the special Do Not Disturb access grant (Settings → Special app access — a settings toggle, not a permission), and without it the worker reports that back and toggles nothing.alertposts a heads-up, sound-on notification on the high-importancerhema-alertchannel with the args'title/body(falling back to "claw" / the action name). Unknown actions are reported, never guessed. -
Notifications: a second periodic worker polls
GET /v1/notifications?device=<id>&since=<cursor>(cursor in DataStore), posts each as a system notification on channelrhema(tap opens the app; the API carries no session key, so it lands on the session list), thenPOSTs an ack per id. Acks are best-effort: the cursor means "seen", not "acked", so a failed ack does not re-notify. -
Permissions:
INTERNET,POST_NOTIFICATIONS(runtime request on API 33+, re-asked per cold start; the OS throttles denials),RECEIVE_BOOT_COMPLETED(boot receiver re-runs the idempotent KEEP schedule; WorkManager also re-enqueues its own work),ACCESS_COARSE_LOCATION/ACCESS_FINE_LOCATION(runtime request per cold start like notifications; a refusal only silences thelocationandwifitopics). Two grants are settings toggles, not permissions: usage access (PACKAGE_USAGE_STATSis declared only so the toggle can grant it) for theapptopic, and Do Not Disturb access (ACCESS_NOTIFICATION_POLICY, declared only so the app appears on the "Do Not Disturb access" screen's list — an undeclared app opens that screen and finds nothing to flip) for the dnd commands. The Status reporting page in Settings shows all three.
API contract (the claw's /v1)
All under one base URL; Authorization: Bearer <token> on /v1, never on
/healthz.
| Endpoint | Used for |
|---|---|
GET /healthz |
settings gate (no auth) |
GET /v1/providers |
backend instances + active pair |
GET /v1/providers/{id}/models |
an instance's live model listing |
PUT /v1/providers/active |
switch the backend instance, persisted |
GET /v1/sessions |
session list |
POST /v1/sessions/{key}/messages |
{"text"} → 202; reply via stream |
GET /v1/sessions/{key}/events |
SSE, replay-then-live: user_message, thinking_delta, text_delta, tool_start, tool_result, turn_done, attachment, consent_request, consent_resolved. ?since=N skips the replay's oldest N events — the transcript cache's cursor |
GET /v1/attachments/{id} |
an attachment event's bytes (bearer) |
GET /v1/consents |
pending consent questions, oldest first |
POST /v1/consents/{id} |
answer one: {"secret"} or {"grant"} |
DELETE /v1/consents/{id} |
deny / cancel a question |
GET /v1/phones |
the device fleet, labels and topics included |
DELETE /v1/phones/{device} |
retire a device's records |
GET /v1/phone/commands?device= |
the control queue for this device |
POST /v1/phone/commands/{id}/result |
execution result; doubles as the ack |
POST /v1/ingest |
{"source","key","payload"} |
GET /v1/notifications?device=&since= |
ascending notification list |
POST /v1/notifications/{id}/ack |
best-effort ack |
Ingest payloads emitted
source is always "phone", key is phone:<deviceId>:<topic>.
Every report is an observation on the claw: it feeds the status the
phone tool reads, and no turn is run (the ingest answers
{"ingested": "observed"}):
{"topic": "battery", "value": "83", "charging": true}
{"topic": "battery", "value": "17", "charging": false}
{"topic": "network", "value": "wifi"} // or "metered" | "offline"
{"topic": "dnd", "value": "on"} // or "off"
{"topic": "location", "lat": 48.85, "lon": 2.35, "accuracy_m": 12.0, "provider": "fused", "age_s": 45}
{"topic": "app", "value": "com.google.android.maps", "label": "Maps", "age_s": 900}
{"topic": "device", "value": "Google Pixel 9", "manufacturer": "Google", "model": "Pixel 9", "android": "16", "sdk": 36, "app_version": "0.1.0"}
{"topic": "wifi", "value": "home"}
{"topic": "alarm", "value": 1760000000000, "in_min": 542}
{"topic": "heartbeat", "ts": 1760000000000}
battery.value is the raw level; the transition rule is charging-flip or
decile bucket change. location posts on a 300 m move from the last posted
fix. app excludes this app itself. wifi needs the location grant
(Android treats an SSID read as location) and is skipped when the system
answers with a placeholder. Unreadable or ungranted sensors produce no
posts for that topic.
Trade-offs
- Notification latency: no push infrastructure; background notifications are as fresh as the WorkManager interval (15 min). The chat screen is always live via SSE.
- Transcript cache: the applied event log persists per session (the newest 500 events plus the full count), so a screen opens on its cached transcript and the stream resumes past it. The cache is a cursor over the claw's record, not a copy of it: a claw database wiped behind the phone's back leaves the cache pointing past a history that no longer exists, and that session replays nothing until it catches up.
- First launch: nothing works until Settings validates
/healthz.
One-consumer principle
The claw's /v1 is the contract. The app has no private endpoints and no
special privileges; every need goes through the same public API any other
client sees. If a feature seems to need a claw change, that change belongs
in the claw's public API first.
Build
Requirements: JDK 17+ (Gradle 9.3.1 runs up to the current JDK; the system
default is fine), Android SDK with platform android-36 (set ANDROID_HOME
or local.properties sdk.dir).
ANDROID_HOME=~/Android/Sdk ./gradlew :app:assembleDebug # debug APK
ANDROID_HOME=~/Android/Sdk ./gradlew :app:lintDebug # lint
ANDROID_HOME=~/Android/Sdk ./gradlew :app:assembleRelease # release APK
APK lands at app/build/outputs/apk/debug/app-debug.apk. Install and run:
adb install app/build/outputs/apk/debug/app-debug.apk
Debug builds are signed with the committed debug.keystore (the standard
Android Debug identity: store/key password android, alias
androiddebugkey), so any build installs over any other: a CI artifact
updates a locally-built install and vice versa. The key is deliberately
not a secret — debug keys guard nothing — a stable signature across
machines is the whole point. The build never touches
~/.android/debug.keystore, so other projects keep their own key.
Release builds are the opposite custody model: the key anchors the
future edge channel — whatever it signs can silently update an install
that trusts the channel — so it never travels with the source. CI holds
it as two repository secrets (ANDROID_RELEASE_KEYSTORE, the base64
keystore, and ANDROID_RELEASE_KEYSTORE_PASSWORD; alias
rhema-release), and the android workflow pins both certificates by
SHA-256 fingerprint before uploading an artifact. Locally, blank
environment leaves assembleRelease unsigned: a build check, never a
deliverable.
Pinned toolchain: Gradle 9.3.1 (wrapper), AGP 8.13.2, Kotlin 2.2.21
(org.jetbrains.kotlin.plugin.compose + plugin.serialization), Compose
BOM 2025.12.01, minSdk 26 / target & compileSdk 36.
Layout
app/src/main/java/rs/rhema/phone/
MainActivity.kt nav state + POST_NOTIFICATIONS runtime request
RhemaApp.kt Application: container, channel, schedule, receiver
di/AppContainer.kt manual DI (OkHttp, Json, repos, api, notifier)
data/ DataStore-backed settings + status repositories
sensors/ the status readers (location, foreground app, wifi, alarm, identity)
net/ ClawApi (one object per endpoint, sealed result type)
chat/ChatController transcript state + SSE loop for the open screen
ui/ Theme, shared design components, SettingsScreen,
SessionsScreen, ChatScreen
work/ PhoneStatusWorker, NotificationsWorker,
PhoneCommandWorker, receivers, scheduling
notif/Notifier.kt channel + system notifications
Cleartext and certificates
The claw is self-hosted, so its address is whatever the operator points
at: a LAN name (kosmos.lan), a bare IP, a Tailscale name, where a
publicly-trusted certificate is rare. The app therefore permits
cleartext HTTP app-wide and trusts user-installed CAs (mkcert installs
into the user store, so a mkcert-secured claw works over HTTPS too).
Only the operator's configured claw is ever contacted, and the bearer
token is the auth; prefer HTTPS wherever the deployment has a real
certificate.
Road notes
- Theming is Jadeite dark, always, the same tokens as the TUI and the
web UI (
crates/rhema-code/src/palette.rsDARK). No light scheme, no dynamic color: the palette is the brand. The screens mirror the web claw's redesign: cards with hairline-divided rows, state dots, badges, toned callouts, avatar-row transcripts with accent-bar tool cards, and the round accent send button; the shared pieces live inui/Components.kt, the Compose counterparts of the web's components. - Future onboarding: scanning a QR code from the claw (base URL + token, rendered by the web UI or printed in the terminal) instead of typing both by hand. Deliberately deferred; the Settings screen is the manual path today.
- Distribution: the CI release artifact (
rhema-android-release) is the future edge channel's payload — publishing it somewhere public (a Gitea generic package, an always-latest link) is deferred; the secret release key is already the channel's trust anchor, so the artifact is worth building and pinning now.