Start here

Quick start

1
Install the Mac app
Open the notarized DMG, drag Carthios into Applications, eject the DMG, then launch the installed copy.
2
Connect Car Thing with a data cable
The first setup and every dashboard/firmware update require USB data—not a charge-only cable.
3
Complete the first-run walkthrough
Carthios installs the matching dashboard automatically and explains Spotify Desktop, dictation, Transit, Agenda, and optional permissions.
4
Choose optional features
Use the Carthios menu-bar icon for Bluetooth Beta, Calendar & Reminders, Transit, Dictation, launch at login, and advanced Spotify.

Connection

USB and Bluetooth Beta

Capability	USB	Bluetooth Beta
Music, Agenda, Transit, timers, system data	Yes	Yes
Initial setup and dashboard/firmware updates	Required	No
Car Thing microphone and dictation	Required	Not yet
Screenshots and recovery	Required	No
Mac sleep and lock brightness mirroring	Yes	Yes

When USB disconnects, Carthios waits briefly for the old connection to close, then reconnects to a previously paired Car Thing over Bluetooth. Plugging USB back in makes USB primary again.

Hardware

Physical controls

Dial

Turn for volume in ten steps. Press for the current page action. Hold Home while turning to adjust brightness.

Home

Press to open Clock. Hold to dictate; recording begins on hold and stops on release.

Preset 1

Press for Now Playing. Hold for Spotify playlists when advanced Spotify is connected.

Preset 2

Press for Pomodoro. Hold for Agenda.

Preset 3

Open the selected Claude Code or Codex monitor.

Preset 4

Open nearby Transit.

Top-right button

Press for Dashboard. Hold for Mac and Car Thing system status.

Screenshot shortcut

Hold Home and the top-right button together. Screenshots require USB.

Product

Feature guide

Spotify Desktop

Artwork, progress, play/pause, skip, seek, shuffle, repeat, podcast seeking, and volume work with the Spotify Mac app already signed in.

Apple Music

Use the same Now Playing screen for songs and Radio, with artwork and metadata when Music provides them, progress, play/pause, skip, seek, shuffle, repeat, and ten-step volume.

Advanced Spotify

Optional Spotify authorization adds account-scoped likes, queue, playlists, following, and Spotify Connect where Spotify supports them.

Transit

Nearby rail and bus departures with refresh time and RAM caching. Supported integrations include MTA, MBTA, WMATA, BART/511, CTA, SEPTA, and TriMet. Some bus sources require a free API key.

Agenda

Upcoming events use their matching macOS Calendar colors. Overdue and due-today reminders appear alongside them and can be completed on Car Thing.

Pomodoro and Clock

A deadline-based timer that survives navigation, a Mac-synchronized clock, offline fallback, and synchronized music progress.

Coding monitor

Choose Claude Code or Codex to see active/recent sessions, completion state, and supported usage warnings.

System monitor

Mac CPU, memory, disk, and battery plus Car Thing temperature and uptime.

Device settings

Brightness, auto brightness, Mac sleep and lock mirroring, time display, Bluetooth controls, first-time setup, recovery, and firmware repair.

Calendar + Reminders

What “Calendar Only” and “Reminders Only” mean

Agenda requests Calendar and Reminders separately. Calendar Only means Calendar access is granted but Reminders is denied or unavailable. Reminders Only means the reverse. Carthios still shows everything macOS permits; the missing half stays empty.

This label does not mean Carthios selected only certain calendars. Open the Carthios menu-bar icon → Calendar & Reminders, then use the Calendar or Reminders action in that submenu. If macOS has never asked, Carthios shows the native consent prompt. If access was already denied, it opens the matching Privacy & Security page. Carthios refreshes the status when you return.

Agenda sends only titles, times, all-day state, display colors, reminder priority, and completion identifiers to Car Thing. Notes, attendees, calendar names, and long-term history are excluded.

Voice

Push-to-talk dictation

1. Click the Mac text field where the result should go.
2. Hold the Car Thing Home button and begin speaking when the listening state appears.
3. Release Home to stop recording and transcribe.

English (US) recognition stays on the Mac. Accessibility is used only for automatic insertion. If it is declined, the finished transcript is copied to the clipboard and Car Thing explains that you can paste it. Smart Cleanup is optional, off by default, Apple Silicon–only, and uses Apple’s supported on-device intelligence path when available.

Privacy

Permissions explained

Automation

Controls the Spotify or Apple Music desktop app you select. macOS may ask the first time Carthios talks to that app.

Speech Recognition

Turns Car Thing microphone audio into text locally on the Mac.

Accessibility

Optional. Inserts finished dictation into the selected text field; clipboard fallback remains available without it.

Bluetooth

Pairs and reconnects to Car Thing wirelessly.

Location

Finds nearby Transit stops. It is not used for advertising or analytics.

Calendars and Reminders

Optional and separate. Powers Agenda only after the user enables it.

Keychain

Stores Spotify and Transit credentials. A repeated password prompt can indicate that the app’s signing identity or saved item access changed.

Files on removable volumes

Not required for normal use. If macOS asks, quit the copy running from the DMG/external drive, drag Carthios to Applications, eject the installer, and launch the installed app.

Optional product diagnostics are separate from macOS permissions and remain off until you enable them. They can record coarse use of Music, Agenda, and Dictation, but never dictated text or audio, music metadata or history, Calendar or Reminder content, credentials, paths, locations, or device identifiers. Read the complete privacy policy.

Display

Dim When Mac Sleeps or Locks

Open the Carthios menu-bar icon → Car Thing → Dim When Mac Sleeps or Locks. When enabled, an authenticated Mac sleep or lock event moves Car Thing to a low-power time and date screen. Its physical backlight follows ambient light within a calibrated nonzero range so the clock remains legible.

Carthios restores the saved manual brightness, or resumes auto brightness, only after the Mac is both awake and unlocked. Inactivity never changes pages, there is no manual sleep button, and Car Thing controls cannot wake the display while the Mac is sleeping or locked. The setting is enabled by default and can be turned off at any time.

Maintenance

Updates and firmware

The Mac app updates through Sparkle with signed, notarized releases. Carthios checks the connected Car Thing dashboard version over USB and installs the matching bundled version when they differ. Firmware/dashboard installation is not available over Bluetooth.

Help

Troubleshooting

Car Thing says the Mac is disconnected

Confirm Carthios is running. For USB, use a data cable. For Bluetooth, pair once in the Car Thing submenu and avoid running USB and Bluetooth simultaneously.

Dictation says no speech or unavailable

Use USB, hold Home before speaking, and release only when finished. Confirm Speech Recognition permission. Accessibility is optional and affects insertion—not transcription.

Agenda is empty

Open the Calendar & Reminders submenu and check whether the status says Calendar Only, Reminders Only, Permission Needed, or Access Denied. For partial access, use the missing-permission button in that submenu.

Buses are missing

Some agencies require a separate free bus API key. Open Transit Settings and read the provider-specific message.

The app asks for removable-drive access

Install in Applications and eject the DMG. Do not keep launching the copy inside the mounted installer.

Bluetooth connects and immediately drops

Connect over USB once so the matching secure Bluetooth bridge is installed, then disconnect USB and allow the Bluetooth handoff to complete.

Roadmap

Requested feature status

Request	Status	Notes
Calendar + Reminders Agenda	Shipped	Events, due reminders, completion, permission states, long-press preset 2, and immediate EventKit-driven updates.
Mac sleep and lock mirroring	Shipped	Optional ambient-aware low-power clock and exact brightness-state restoration over USB or Bluetooth.
Apple Music	Shipped	Switch directly from the Mac menu for songs and Radio with metadata, artwork, progress, playback, seeking, ten-step volume, shuffle, and repeat.
YouTube Music	Research	No reliable supported desktop control integration has shipped.
Bluetooth dictation	Research	Current microphone transport requires USB data.
Bluetooth firmware updates	Not supported	Updates require USB for recovery safety and reliable filesystem transfer.
On-device wake word and voice commands	Research	Hardware cost, false activation, privacy, and offline model constraints are still being evaluated.
Smarter local dictation	Partial	On-device recognition, punctuation, and optional Smart Cleanup ship; broader Whisper Flow-style rewriting is limited to supported Apple Intelligence APIs.
Lyrics and audiobook transcription	Deferred	Work is paused by product decision.
Spotify playback without another login	Shipped	Core controls use the signed-in Spotify Desktop app; account-scoped features still require optional Spotify authorization.
Privacy-first product diagnostics	Shipped	Optional, off by default, and limited to coarse allowlisted usage and reliability events. Dictated text/audio, music metadata/history, Agenda content, location, credentials, and device identifiers are excluded.