Quick start: Go

Start a session on a device, launch Settings, tap a row, take a screenshot, and quit — from Go. Starts with mobium.Start(ctx, mobium.WithPlatform(...), mobium.WithApp(...)); ends with device.Quit(ctx).

Before this page: install mobium and prepare a device.

1. What you need

Go 1.24 or later.

2. Install the client

The Go module is published through GitHub, so this works today.

mkdir quickstart && cd quickstart
go mod init quickstart
go get github.com/mobiumdev/mobium/clients/go

3. The code

Save this as main.go in the project folder — it is examples/go/main.go.

// Mobium quick start: start a session, drive Settings, quit.
//
//	MOBIUM_PLATFORM=android go run .    # or ios
package main

import (
	"context"
	"fmt"
	"log"
	"os"
	"strings"
	"time"

	mobium "github.com/mobiumdev/mobium/clients/go"
)

// Settings is on every emulator, simulator and phone, with nothing to install.
var platforms = map[string]struct{ app, row, next string }{
	"android": {"com.android.settings", "Network & internet", "text=Airplane mode"},
	"ios":     {"com.apple.Preferences", "General", "label=About,role=button"},
}

func main() {
	platform := os.Getenv("MOBIUM_PLATFORM")
	if platform == "" {
		platform = "android"
	}
	p := platforms[platform]
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
	defer cancel()

	// 1. Start the session: the driver is started on the device and Settings
	//    is launched.
	opts := []mobium.Option{mobium.WithPlatform(platform), mobium.WithApp(p.app)}
	if d := os.Getenv("MOBIUM_DEVICE"); d != "" {
		opts = append(opts, mobium.WithDevice(d))
	}
	device, err := mobium.Start(ctx, opts...)
	if err != nil {
		log.Fatal(err)
	}
	// 5. Quit when main returns: the device's session is closed.
	defer func() {
		if err := device.Quit(ctx); err != nil {
			log.Fatal(err)
		}
		fmt.Println("session ended")
	}()
	s := device.Session()
	fmt.Printf("session on %s (%s, %s)\n", s.Device, s.Platform, s.Driver)

	// 2. Map the screen: every element you can act on, each with a @ref.
	elements, err := device.Map(ctx)
	if err != nil {
		log.Fatal(err)
	}
	for _, e := range elements[:min(5, len(elements))] {
		fmt.Println(" ", e.Ref, e.Label, "("+e.Role+")")
	}

	// 3. Tap a row by its ref, then wait for the screen it opens. A row's
	//    label can carry its summary too ("Network & internet Mobile, Wi-Fi,
	//    ..."), so match its start.
	ref := ""
	for _, e := range elements {
		if strings.HasPrefix(e.Label, p.row) {
			ref = e.Ref
			break
		}
	}
	if ref == "" {
		log.Fatalf("no row starting with %q", p.row)
	}
	if err := device.Tap(ctx, ref); err != nil {
		log.Fatal(err)
	}
	if _, err := device.WaitFor(ctx, p.next, nil); err != nil {
		log.Fatal(err)
	}
	fmt.Println("opened", p.row)

	// 4. Take a screenshot.
	name := "quickstart-" + platform + ".png"
	if _, err := device.Screenshot(ctx, name); err != nil {
		log.Fatal(err)
	}
	fmt.Println("saved", name)
}

Settings is on every Android and iOS device with nothing to install. The row and the screen after it are the only things that differ by platform.

4. Run it

Android

MOBIUM_PLATFORM=android go run .

What it printed on an Android 15 emulator:

waiting for the UiAutomator2 server to start...
session on emulator-5554 (android, uiautomator2)
  @e1 settings_homepage_container (list)
  @e2 Profile picture, double tap to open Google Account (button)
  @e3 Search settings (button)
  @e4 main_content_scrollable_container (list)
  @e5 Network & internet Mobile, Wi‑Fi, hotspot (button)
opened Network & internet
saved quickstart-android.png
session ended

After start	After the tap

iOS

MOBIUM_PLATFORM=ios go run .

What it printed on an iOS 26.5 simulator:

waiting for WebDriverAgent to start...
session on 457C7DC2-C706-45D9-8D68-1D26953E28B1 (ios, wda)
  @e1 Apple Account, Sign in to access your iCloud data, the App Store, Apple services, and more. (button)
  @e2 General (button)
  @e3 Accessibility (button)
  @e4 Action Button (button)
  @e5 Apple Intelligence & Siri (button)
opened General
saved quickstart-ios.png
session ended

After start	After the tap

The first start on a device is slow: it installs the UiAutomator2 server on Android, and on a real iPhone builds WebDriverAgent. Later starts take seconds.

Notes

• defer device.Quit(ctx) right after a successful Start is the usual shape. A second Quit does nothing, so an explicit one before it is fine.
• The example in the repository builds against the client beside it, through a replace line in its go.mod; your own module uses go get.
• mobium.Connect still exists: it opens a connection without touching the device, and Close leaves the session open.
• With more than one device of the session's platform running — two Android devices, or two among the booted simulators and attached iPhones — start refuses to guess and lists them. One Android device and one iOS device are not ambiguous: the platform picks. Name one with MOBIUM_DEVICE=<serial or UDID>, which the example passes on as the device.

Next: the rest of the tool surface, and setting up phones and simulators. Changing the client itself? DEVELOPMENT.md is the contributor's guide.