Android

Android Device Mastery

This skill covers everything about interacting with Android devices via ADB and shell commands.

Device Connection

Check Connected Devices

adb devices -l

Output shows serial, status, and device info. Common statuses:

• device - Connected and authorized
• unauthorized - Accept USB debugging prompt on device
• offline - Connection issues, try adb kill-server && adb start-server

Wireless Debugging

Android 11+ (Recommended):

1. Enable Wireless debugging in Developer Options 2. Tap "Pair device with pairing code" 3. Run: adb pair <ip>:<pairing_port> and enter the code 4. Then: adb connect <ip>:<connection_port>

Legacy (requires USB first):

adb tcpip 5555
adb connect <device_ip>:5555

Multiple Devices

Always specify device with -s:

adb -s <serial> shell
adb -s emulator-5554 install app.apk

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Shell Commands

Interactive Shell

adb shell                    # Enter shell
adb shell <command>          # Run single command
adb shell "cmd1 && cmd2"     # Chain commands

Essential Commands

# Device info
getprop ro.product.model              # Device model
getprop ro.build.version.release      # Android version
getprop ro.build.version.sdk          # SDK level

# File operations
ls -la /sdcard/
cat /path/to/file
cp /source /dest
rm /path/to/file

# Process info
ps -A | grep <name>
pidof <package_name>
top -n 1 -m 10

Safe Output Limiting

For commands with potentially large output:

adb shell "logcat -d | head -500"
adb shell "dumpsys activity | head -200"

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App Management

Install/Uninstall

adb install app.apk                   # Basic install
adb install -r app.apk                # Replace existing
adb install -g app.apk                # Grant all permissions
adb install -r -g app.apk             # Both

adb uninstall com.example.app         # Full uninstall
adb uninstall -k com.example.app      # Keep data

Start/Stop Apps

# Start main activity
adb shell monkey -p com.example.app -c android.intent.category.LAUNCHER 1

# Start specific activity
adb shell am start -n com.example.app/.MainActivity

# Start with intent extras
adb shell am start -n com.example.app/.Activity \
    -a android.intent.action.VIEW \
    -d "myapp://page/123" \
    --es "key" "value"

# Force stop
adb shell am force-stop com.example.app

# Clear app data
adb shell pm clear com.example.app

List Packages

adb shell pm list packages              # All packages
adb shell pm list packages -3           # Third-party only
adb shell pm list packages | grep term  # Filter

adb shell pm path com.example.app       # APK location
adb shell dumpsys package com.example.app  # Full package info

Permissions

adb shell pm grant com.example.app android.permission.CAMERA
adb shell pm revoke com.example.app android.permission.CAMERA
adb shell dumpsys package com.example.app | grep permission

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File Operations

Push/Pull Files

adb push local_file.txt /sdcard/
adb pull /sdcard/remote_file.txt ./

# Recursive
adb push local_dir/ /sdcard/target/
adb pull /sdcard/dir/ ./local/

Access App Data (Debuggable Apps)

adb shell run-as com.example.app ls files/
adb shell run-as com.example.app cat shared_prefs/prefs.xml
adb shell run-as com.example.app sqlite3 databases/app.db ".tables"

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UI Automation

Input Commands

# Tap at coordinates
adb shell input tap 500 800

# Swipe (x1 y1 x2 y2 [duration_ms])
adb shell input swipe 500 1500 500 500 300

# Text input (needs focused field)
adb shell input text "hello"

# Key events
adb shell input keyevent KEYCODE_HOME      # Home
adb shell input keyevent KEYCODE_BACK      # Back
adb shell input keyevent KEYCODE_ENTER     # Enter
adb shell input keyevent KEYCODE_POWER     # Power
adb shell input keyevent KEYCODE_VOLUME_UP # Volume up

Common Keycodes

Screenshots & Recording

# Screenshot
adb shell screencap -p /sdcard/screen.png
adb pull /sdcard/screen.png

# One-liner (binary-safe)
adb exec-out screencap -p > screen.png

# Screen recording (max 3 min)
adb shell screenrecord /sdcard/video.mp4
adb shell screenrecord --time-limit 10 /sdcard/video.mp4

UI Hierarchy

adb shell uiautomator dump /sdcard/ui.xml
adb pull /sdcard/ui.xml

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Debugging & Logs

Logcat Essentials

# Dump and exit
adb logcat -d

# Last N lines
adb logcat -t 100

# Filter by tag:priority
adb logcat ActivityManager:I *:S

# Filter by package (get PID first)
adb logcat --pid=$(adb shell pidof -s com.example.app)

# Crash buffer
adb logcat -b crash

Priority levels: V(erbose), D(ebug), I(nfo), W(arn), E(rror), F(atal), S(ilent)

Common Debug Patterns

# Find crashes
adb logcat *:E | grep -E "(Exception|Error|FATAL)"

# Activity lifecycle
adb logcat ActivityManager:I ActivityTaskManager:I *:S

# Memory issues
adb logcat art:D dalvikvm:D *:S | grep -i "gc"

Memory Analysis

adb shell dumpsys meminfo com.example.app

Key metrics:

• PSS: Proportional memory use (compare apps with this)
• Private Dirty: Memory exclusive to process
• Heap: Java/Native heap usage

Crash Analysis

# ANR traces
adb shell cat /data/anr/traces.txt

# Tombstones (native crashes, needs root)
adb shell ls /data/tombstones/

# Recent crashes via logcat
adb logcat -b crash -d

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System Inspection

dumpsys Services

adb shell dumpsys -l                    # List all services

# Common services
adb shell dumpsys activity              # Activities, processes
adb shell dumpsys package <pkg>         # Package details
adb shell dumpsys battery               # Battery status
adb shell dumpsys meminfo               # System memory
adb shell dumpsys cpuinfo               # CPU usage
adb shell dumpsys window displays       # Display info
adb shell dumpsys connectivity          # Network state

System Properties

adb shell getprop                       # All properties
adb shell getprop | grep <filter>       # Filter properties

# Useful properties
getprop ro.product.model                # Model
getprop ro.build.fingerprint            # Build fingerprint
getprop ro.serialno                     # Serial number
getprop sys.boot_completed              # Boot status (1 = done)

Settings

# Namespaces: system, secure, global
adb shell settings get global airplane_mode_on
adb shell settings put system screen_brightness 128
adb shell settings list global

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Reboot Commands

adb reboot                   # Normal reboot
adb reboot recovery          # Recovery mode
adb reboot bootloader        # Fastboot mode
adb reboot sideload          # Sideload mode
adb reboot-bootloader        # Alias for bootloader

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Troubleshooting

Device not found:

adb kill-server && adb start-server

Unauthorized:

• Check USB debugging is enabled
• Revoke USB debugging authorizations in Developer Options, reconnect

Multiple devices error:

• Use -s <serial> to specify device

Command not found (on device):

• Some commands require root or are version-specific
• Try /system/bin/<cmd> or check if command exists

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Quick Reference

For deep dives into specific topics, see references/deep-dive.md.

Android Deep Dive Reference

Extended reference for advanced Android device operations.

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Advanced Logcat

Buffer Selection

adb logcat -b main       # App logs (default)
adb logcat -b system     # System logs
adb logcat -b crash      # Crashes only
adb logcat -b radio      # Telephony
adb logcat -b events     # System events
adb logcat -b kernel     # Kernel (like dmesg)
adb logcat -b all        # Everything

Output Formats

adb logcat -v brief      # Tag and priority
adb logcat -v time       # With timestamps
adb logcat -v threadtime # Time + PID + TID (recommended)
adb logcat -v long       # Full metadata
adb logcat -v color      # Colorized

Advanced Filtering

# Multiple tags
adb logcat "ActivityManager:I MyApp:D *:S"

# By UID
adb logcat --uid=10123

# Since timestamp
adb logcat -T "01-25 14:00:00.000"

# Clear buffer
adb logcat -c

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Comprehensive dumpsys

Activity Manager (Most Used)

adb shell dumpsys activity activities    # Activity stacks
adb shell dumpsys activity services      # Running services
adb shell dumpsys activity broadcasts    # Broadcast queues
adb shell dumpsys activity processes     # Process list
adb shell dumpsys activity recents       # Recent tasks
adb shell dumpsys activity top           # Current activity
adb shell dumpsys activity lastanr       # Last ANR
adb shell dumpsys activity package <pkg> # Per-package info
adb shell dumpsys activity exit-info     # Exit reasons (Android 11+)

Package Manager

adb shell dumpsys package <pkg>          # Full package dump
adb shell dumpsys package packages       # All packages
adb shell dumpsys package permissions    # Permission definitions
adb shell dumpsys package features       # Device features
adb shell dumpsys package dexopt         # DEX optimization state

Battery & Power

adb shell dumpsys battery                # Current status
adb shell dumpsys batterystats           # Detailed stats
adb shell dumpsys batterystats --charged # Since last charge
adb shell dumpsys power                  # Wake locks
adb shell dumpsys deviceidle             # Doze state

Network

adb shell dumpsys connectivity           # Network state
adb shell dumpsys wifi                   # WiFi details
adb shell dumpsys netstats               # Network usage

Graphics & Performance

adb shell dumpsys gfxinfo <pkg>          # Frame stats
adb shell dumpsys gfxinfo <pkg> framestats  # Detailed timing
adb shell dumpsys meminfo <pkg>          # Memory breakdown
adb shell dumpsys procstats --hours 3    # Process stats
adb shell dumpsys cpuinfo                # CPU usage

Other Useful Services

adb shell dumpsys notification           # Notifications
adb shell dumpsys alarm                  # Scheduled alarms
adb shell dumpsys location               # Location providers
adb shell dumpsys sensorservice          # Sensors
adb shell dumpsys input                  # Input devices
adb shell dumpsys display                # Display config
adb shell dumpsys usb                    # USB state
adb shell dumpsys dropbox                # System crash logs

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Process Debugging

Process Inspection

adb shell ps -A                          # All processes
adb shell ps -A | grep <pkg>             # Filter by name
adb shell ps -T -p <pid>                 # Threads for PID
adb shell top -n 1 -s cpu                # Top by CPU
adb shell top -n 1 -s res                # Top by memory

/proc Filesystem

# Process status
adb shell cat /proc/<pid>/status

# Memory maps
adb shell cat /proc/<pid>/maps

# Open file descriptors
adb shell ls -la /proc/<pid>/fd

# Command line
adb shell cat /proc/<pid>/cmdline

# System memory
adb shell cat /proc/meminfo

# CPU info
adb shell cat /proc/cpuinfo

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Performance Profiling

Heap Dumps

# Java heap (for Android Studio / MAT)
adb shell am dumpheap <pid> /sdcard/heap.hprof
adb pull /sdcard/heap.hprof
hprof-conv heap.hprof heap-converted.hprof

# Native heap (requires root)
adb shell am dumpheap -n <pid> /sdcard/native.hprof

Method Tracing

adb shell am profile start <pkg> /sdcard/profile.trace
# ... perform actions ...
adb shell am profile stop <pkg>
adb pull /sdcard/profile.trace

GPU Profiling

adb shell dumpsys gfxinfo <pkg>
adb shell dumpsys gfxinfo <pkg> framestats

# Enable overdraw visualization
adb shell setprop debug.hwui.overdraw show

# GPU debug layers (Vulkan)
adb shell settings put global enable_gpu_debug_layers 1
adb shell settings put global gpu_debug_app <pkg>

Perfetto/Systrace

# Record system trace
adb shell perfetto --txt -c /etc/perfetto/configs/sched_trace.pbtxt \
    -o /data/misc/perfetto-traces/trace.perfetto-trace
adb pull /data/misc/perfetto-traces/trace.perfetto-trace
# Open at https://ui.perfetto.dev

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Crash Analysis

Tombstones (Native Crashes)

adb shell ls -la /data/tombstones/
adb shell cat /data/tombstones/tombstone_00
adb pull /data/tombstones/

Key sections:

• Signal (SIGSEGV, SIGABRT, etc.)
• Fault address
• Register state
• Backtrace

Symbolication

ndk-stack -sym /path/to/symbols -dump tombstone_00
adb logcat | ndk-stack -sym /path/to/symbols

ANR Analysis

adb shell cat /data/anr/traces.txt      # Older devices
adb shell cat /data/anr/anr_*           # Newer devices

Look for:

• Main thread state
• Lock contention
• Long operations on main thread

DropBox Entries

adb shell dumpsys dropbox
adb shell dumpsys dropbox --print data_app_crash
adb shell dumpsys dropbox --print data_app_anr

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Network Debugging

Connection Info

adb shell cat /proc/net/tcp
adb shell cat /proc/net/udp
adb shell netstat -an                   # If available
adb shell ss -tunap                     # Modern alternative

Proxy Setup

adb shell settings put global http_proxy <ip>:<port>
adb shell settings put global http_proxy :0  # Remove

Packet Capture

adb shell tcpdump -i any -w /sdcard/capture.pcap
adb pull /sdcard/capture.pcap
# Open in Wireshark

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UI Automation Advanced

All Keycodes

# Navigation
KEYCODE_DPAD_UP=19, DOWN=20, LEFT=21, RIGHT=22, CENTER=23

# Media
KEYCODE_MEDIA_PLAY_PAUSE=85, NEXT=87, PREVIOUS=88
KEYCODE_VOLUME_MUTE=164

# System
KEYCODE_WAKEUP=224, KEYCODE_SLEEP=223
KEYCODE_APP_SWITCH=187 (Recent apps)
KEYCODE_SYSRQ=120 (Screenshot)

Long Press

# Simulate long press with swipe of 0 distance
adb shell input swipe 500 500 500 500 1000

Text with Special Characters

# Escape spaces
adb shell input text "hello%sworld"  # %s = space

# For complex text, use keyboard broadcast
adb shell am broadcast -a ADB_INPUT_TEXT --es msg "Hello World!"

Window Manager

adb shell wm size                       # Screen size
adb shell wm density                    # DPI
adb shell wm size 1080x1920             # Override size
adb shell wm size reset                 # Reset

adb shell wm overscan 0,0,0,200         # Add overscan

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Content Providers

# Query
adb shell content query --uri content://settings/system

# Insert
adb shell content insert --uri content://settings/system \
    --bind name:s:my_setting --bind value:s:my_value

# Update
adb shell content update --uri content://settings/system \
    --where "name='my_setting'" --bind value:s:new_value

# Delete
adb shell content delete --uri content://settings/system \
    --where "name='my_setting'"

# Common URIs
content://contacts/people
content://sms/inbox
content://settings/system
content://settings/secure
content://settings/global

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Service Calls

adb shell service list                  # List services
adb shell service call <service> <code> # Call service method

cmd Interface (Android 8+)

adb shell cmd -l                        # List services
adb shell cmd package list packages
adb shell cmd activity start -n <component>
adb shell cmd statusbar expand-notifications
adb shell cmd battery set level 50

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Developer Options via ADB

# Stay awake while charging
adb shell settings put global stay_on_while_plugged_in 3

# Show touches
adb shell settings put system show_touches 1

# Pointer location
adb shell settings put system pointer_location 1

# Animation scales (0 = off, good for testing)
adb shell settings put global window_animation_scale 0
adb shell settings put global transition_animation_scale 0
adb shell settings put global animator_duration_scale 0

# Force GPU rendering
adb shell settings put global force_gpu true

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Emulator-Specific

# Telnet to emulator console
telnet localhost 5554

# In console:
sms send 5551234567 "Hello"
geo fix -122.084 37.422
power capacity 50
network speed gsm

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Quick Diagnostics Script

#!/bin/bash
# android-diag.sh - Quick device diagnostics

echo "=== Device Info ==="
adb shell getprop ro.product.model
adb shell getprop ro.build.version.release

echo "=== Memory ==="
adb shell cat /proc/meminfo | head -5

echo "=== Storage ==="
adb shell df -h /data

echo "=== Battery ==="
adb shell dumpsys battery | grep -E "level|status|health"

echo "=== Top Processes ==="
adb shell top -n 1 -m 5 -s res

echo "=== Recent Crashes ==="
adb logcat -b crash -d -t 10 2>/dev/null || echo "No recent crashes"