Mobile Next Device Kit

A set of tools for controlling Android devices and reading device state that is not possible through adb shell alone. The tools run headless via app_process straight from a single classes.dex — nothing needs to be installed on the device.

Features

• Clipboard — get, set (incl. base64), and clear the system clipboard
• UI tree dump — dump the on-screen accessibility hierarchy as JSON
• Package list — list installed packages with app name and version
• Screen streaming — H.264 (AVC) or MJPEG, with scale/fps/quality options

All of the above run from the published devicekit.dex with no app install.

Installing

Download the latest devicekit.dex from GitHub releases and push it to the device:

curl -s -O -J -L https://github.com/mobile-next/devicekit-android/releases/latest/download/devicekit.dex
adb push devicekit.dex /data/local/tmp/

Usage

Every tool is launched the same way — app_process with the dex on the classpath:

adb shell CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.<Tool> [args]

The tools run as the shell user (uid 2000); no root is required.

For tools that emit binary output (the screen streamers) use adb exec-out instead of adb shell, otherwise the stream is corrupted by newline translation.

Clipboard

# Set the clipboard
adb shell CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.Clipboard set "Hello World"

# Set from base64 (safest for spaces, emoji, and other UTF-8) — "✌️"
adb shell CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.Clipboard set --base64 "4pyM77iP"

# Print the current clipboard text
adb shell CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.Clipboard get

# Clear the clipboard
adb shell CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.Clipboard clear

Since devicekit cannot force a keypress, paste with:

adb shell input keyevent KEYCODE_PASTE

Dump the UI view tree

Prints the current accessibility hierarchy as JSON to stdout:

adb shell CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.UiDump

Optionally wait up to N milliseconds for the UI to go idle first (useful right after a navigation or transition):

adb shell CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.UiDump 2000

List installed packages

Prints a JSON array of {packageName, appName, version}:

adb shell CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.PackageLister

Stream the screen as H.264 (AVC)

Writes a raw H.264 (Annex-B) elementary stream to stdout:

adb exec-out CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.AvcServer --scale 0.5 --fps 30 > screen.h264

Pipe it straight into a player:

adb exec-out CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.AvcServer | ffplay -probesize 32 -sync ext -

Parameter	Type	Default	Description
--bitrate	int (bps)	10000000	Target bitrate (min 100000)
--scale	float	1.0	Output scale, 0.1–2.0
--fps	int	30	Frame rate, 1–60

Stream the screen as MJPEG

Writes a multipart/x-mixed-replace MJPEG stream to stdout:

adb exec-out CLASSPATH=/data/local/tmp/devicekit.dex app_process / com.mobilenext.devicekit.MjpegServer --quality 80 --scale 0.5 --fps 30 > screen.mjpeg

Parameter	Type	Default	Description
--quality	int	80	JPEG quality, 1–100
--scale	float	1.0	Output scale, 0.1–2.0
--fps	int	30	Frame rate, 1–60

Resident JSON-RPC server (advanced)

For repeated UI queries, DeviceKitServer starts once and stays resident, answering JSON-RPC over a persistent socket instead of paying process startup on every call. It is instrumentation-based, so it requires the APK to be installed (build it from source — see below):

# Start the server (leave running or background it)
adb shell am instrument -w com.mobilenext.devicekit/.DeviceKitServer

It listens on localabstract:devicekit. Forward a local port and query it:

adb forward tcp:8080 localabstract:devicekit

curl -s http://localhost:8080 \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"device.dump.ui","params":{"waitUntilIdle":2000}}'

adb forward --remove tcp:8080

Building from source

./gradlew assembleDebug

The dex used by all the app_process tools is inside the built APK:

unzip -o -j app/build/outputs/apk/debug/app-debug.apk classes.dex -d .
adb push classes.dex /data/local/tmp/devicekit.dex

To use the instrumentation-based resident server, install the APK instead:

adb install app/build/outputs/apk/debug/app-debug.apk

Requirements

• Android 10 (API 29) or newer
• Tools run in the adb shell (uid 2000) context; no root required