mobster expo

Open your Expo app on a simulator or your iPhone from the JavaScript Metro serves, in your dev client or Expo Go, and check a screen. Build it for checks and CI: Release for the simulator, with the JavaScript inside, or your dev client on your iPhone.

Usage

mobster expo <command>

examples:
  mobster expo preview --device "Test iPhone" --expect "Welcome back"
  mobster expo reload
  mobster expo build
  mobster expo build --device "Test iPhone"

Commands

Command	What it does
`mobster expo doctor`	say what Mobster found in this Expo or React Native project
`mobster expo preview`	open the app on a simulator or your iPhone from Metro, and check a screen
`mobster expo dev`	run the dev loop: Metro, the dev client, the app open, a reload on every save
`mobster expo reload`	reload the JavaScript in every app connected to Metro
`mobster expo build`	build the app for a simulator or your iPhone
`mobster expo stop`	stop the Metro that `mobster expo preview` started

`mobster expo doctor`

Read package.json and the Expo config, and say what Mobster found: the app’s name, bundle ID and schemes, whether it opens in your dev client or Expo Go, whether the ios folder exists, and whether Metro is running. Reads only.

Options

Name	Default	Description
`--port N`	8081	Metro’s port
`--json`	off	print it as JSON

`mobster expo preview`

Open your app on a simulator or your iPhone from the JavaScript Metro serves from your working tree: in your dev client when the app has expo-dev-client, else in Expo Go. Starts Metro in the background when nothing answers on the port. With --expect, waits for the text and says whether it’s on screen, with a screenshot.

Options

Name	Default	Description
`--device NAME`	your iPhone, else the only device	a device from `mobster devices`
`--port N`	8081	Metro’s port
`--path PATH`	none	then open this screen by the app’s own deep link, such as settings/profile
`--expect TEXT`	none	text that must be on screen once the app loads; repeatable
`--wait S`	45	how long `--expect` waits for the bundle to load
`--no-start`	off	don’t start Metro; fail when it isn’t running
`--screenshot FILE`	with `--expect`: .mobster/expo/preview.png	save the screen here
`--json`	off	print the result as JSON

exit codes: 0 opened (and every expectation held), 1 an expectation didn't hold, 3 couldn't

examples:
  mobster expo preview
  mobster expo preview --device "Test iPhone" --expect "Welcome back"
  mobster expo preview --path settings/profile --expect Profile

`mobster expo dev`

Start this project’s Metro (or reuse it), install your dev client on the device when it isn’t there, open the app, and reload it each time you save a source file. When Metro can’t bundle the app, it says so with Metro’s error and keeps watching: the next save tries again. ctrl+c stops the Metro this command started. --check runs saved checks on the device once the app is up.

Options

Name	Default	Description
`--device NAME`	your iPhone, else the only device	a device from `mobster devices`
`--port N`	8081, else the next free one	Metro’s port
`--check PATH`	none	a check file or folder to run on the device once the app is up; repeatable
`--no-install`	off	don’t build and install the dev client when it is missing
`--once`	off	open the app, run the checks, and stop; no watching
`--json`	off	print one JSON line per event

exit codes: 0 stopped with ctrl+c (or --once: opened and every check held), 1 Metro can't bundle the app or a check didn't hold, 3 couldn't

examples:
  mobster expo dev --device "Test iPhone"
  mobster expo dev --once --check .mobster/checks/home.yaml

`mobster expo reload`

Send Metro’s reload to every app connected to it, as pressing r in npx expo start does.

Options

Name	Default	Description
`--port N`	8081	Metro’s port

`mobster expo build`

Build the app. For a simulator: a Release build into .mobster/build with the JavaScript inside, so it runs with no Metro (what checks and CI use), after npx expo prebuild when there’s no ios folder. For an iPhone: your dev client, signed with your team and installed by npx expo run:ios --device. --eas builds an EAS profile on this Mac with eas build --local.

Options

Name	Default	Description
`--device NAME`	none	build for this device: an iPhone (installs your dev client) or a Mobster simulator
`--install`	off	install the build on `--device`
`--debug`	off	a Debug build that loads its JavaScript from Metro (the dev client), not Release
`--eas PROFILE`	none	build this EAS profile on this Mac (eas build `--local`)
`--json`	off	print the build as JSON

examples:
  mobster expo build
  mobster expo build --device "iPhone 17 Pro" --install
  mobster expo build --device "Test iPhone"
  mobster expo build --eas development --device "Test iPhone" --install

`mobster expo stop`

Stop the Metro server mobster expo preview started in the background for this project.

CLI

MCP

Settings and errors

Inside Mobster

Usage

Commands

`mobster expo doctor`

Options

`mobster expo preview`

Options

`mobster expo dev`

Options

`mobster expo reload`

Options

`mobster expo build`

Options

`mobster expo stop`

​Usage

​Commands

​mobster expo doctor

​Options

​mobster expo preview

​Options

​mobster expo dev

​Options

​mobster expo reload

​Options

​mobster expo build

​Options

​mobster expo stop

Usage

Commands

`mobster expo doctor`

Options

`mobster expo preview`

Options

`mobster expo dev`

Options

`mobster expo reload`

Options

`mobster expo build`

Options

`mobster expo stop`