📵 Phone Blocker

A simple Android app to block unwanted calls using pattern matching with wildcards.

🌐 Live Preview | 📦 Download APK

Features

• Pattern Matching - Flexible wildcards for matching phone numbers
  • * = match zero or more digits
  • ? = match exactly one digit
  • 86* blocks ALL numbers starting with 86
  • 138???????? blocks 11-digit numbers starting with 138
• Four Actions:
  • ✅ Allow - Whitelist (highest priority, checked first)
  • 🚫 Block - Reject the call completely
  • 🔇 Silence - Mute ringer, call still visible
  • 📞 Voicemail - Decline to voicemail
• Priority System - ALLOW rules are always checked first
• Call Log - View incoming calls with raw number format
• Enable/Disable - Toggle individual rules on/off
• Simple UI - Easy to add, manage, and delete rules

Requirements

• Android 10+ (API 29+)
• Permissions: Phone, Call Logs

Installation

From GitHub Releases (Recommended)

1. Download the latest APK from Releases
2. Enable "Install from unknown sources" in Settings
3. Open the APK file to install
4. Launch the app and grant permissions when prompted

Setup Permissions

After installing, you need to grant permissions:

1. Settings → Apps → Phone Blocker → Permissions

   • Enable: Phone (电话)
   • Enable: Call Logs (通话记录)

2. Set as Call Screening App (if prompted):

   • Settings → Apps → Default Apps → Caller ID & Spam
   • Select: Phone Blocker

Note: Some phones (especially Chinese ROMs like MIUI, ColorOS, etc.) may not show the Call Screening option. The app includes a fallback method that works on most devices.

Usage

Adding Rules

1. Tap the + button
2. Enter pattern using digits and wildcards (* ?)
3. Select action: Allow, Block, Silence, or Voicemail
4. Tap Add

Pattern Matching

The app strips all non-digit characters from incoming numbers before matching:

• +8613812345678 becomes 8613812345678
• 183+23456312 becomes 18323456312
• (021) 555-1234 becomes 0215551234

Wildcards

Wildcard	Meaning	Example
*	Zero or more digits	86* matches 86, 861, 8612345678
?	Exactly one digit	138???????? matches any 11-digit number starting with 138

Pattern Examples

Pattern	Matches	Use Case
86*	All numbers starting with 86	Block all China numbers
865*	Numbers starting with 865	Allow specific prefix (use with ALLOW)
138????????	11-digit numbers starting with 138	Block specific carrier prefix
1800*	Numbers starting with 1800	Block toll-free numbers
????1234	8-digit numbers ending with 1234	Block numbers with specific suffix
*	ALL numbers	Block everything (use ALLOW rules for exceptions)

Priority & Whitelist Example

To block all China numbers EXCEPT a specific prefix:

1. Add rule: 865* → Allow (checked first)
2. Add rule: 86* → Block (checked second)

Result: 8651234567 is allowed, 8612345678 is blocked.

Call Log

Tap 📋 Log to view incoming calls:

• Shows raw phone number format
• Shows matched pattern (if any)
• Status: ALLOW, BLOCK, SILENCE, VOICEMAIL, or NOT MATCH

Building from Source

Prerequisites

• JDK 17
• Android SDK (API 34)
• Gradle 8.2+

Linux

# Install JDK 17
sudo apt install openjdk-17-jdk

# Set up Android SDK
mkdir -p ~/Android/cmdline-tools
cd ~/Android/cmdline-tools
wget https://dl.google.com/android/repository/commandlinetools-linux-11076708_latest.zip
unzip commandlinetools-linux-11076708_latest.zip
mv cmdline-tools latest

# Set environment variables
export JAVA_HOME=/usr/lib/jvm/java-17-openjdk-amd64
export ANDROID_HOME=~/Android
export PATH=$PATH:$ANDROID_HOME/cmdline-tools/latest/bin:$ANDROID_HOME/platform-tools

# Install SDK components
yes | sdkmanager --licenses
sdkmanager "platform-tools" "platforms;android-34" "build-tools;34.0.0"

# Clone and build
git clone https://github.com/johnwmail/phone-blocker.git
cd phone-blocker
./gradlew assembleDebug

# APK will be at:
# app/build/outputs/apk/debug/app-debug.apk

Windows

1. Install JDK 17
2. Install Android Studio (includes SDK)
3. Open project in Android Studio
4. Build → Build Bundle(s) / APK(s) → Build APK(s)

Run Tests

./gradlew testDebugUnitTest

Project Structure

phone-blocker/
├── .github/workflows/
│   ├── test.yml                 # CI: test & lint on push/PR
│   └── release.yml              # CI: build & release on tag
├── docs/                        # GitHub Pages
│   ├── index.html               # Download page
│   └── preview.html             # Interactive UI preview
├── app/
│   ├── src/main/
│   │   ├── java/com/phoneblocker/
│   │   │   ├── MainActivity.kt       # Main UI
│   │   │   ├── BlockRule.kt          # Rule data model & matching
│   │   │   ├── RuleStorage.kt        # Save/load rules (with priority)
│   │   │   ├── RuleAdapter.kt        # RecyclerView adapter
│   │   │   ├── CallBlockerService.kt # CallScreeningService (Android 10+)
│   │   │   ├── CallReceiver.kt       # BroadcastReceiver fallback
│   │   │   ├── CallLogActivity.kt    # Call log viewer
│   │   │   └── CallLogStorage.kt     # Call log storage
│   │   ├── res/
│   │   │   ├── layout/               # UI layouts
│   │   │   ├── menu/                 # Menu resources
│   │   │   ├── values/               # Colors, strings, themes
│   │   │   └── drawable/             # Icons
│   │   └── AndroidManifest.xml
│   ├── src/test/
│   │   └── java/com/phoneblocker/
│   │       └── BlockRuleTest.kt      # Unit tests
│   └── build.gradle.kts
├── build.gradle.kts
├── settings.gradle.kts
└── README.md

How It Works

Call Blocking Methods

The app uses two methods to block calls:

1. CallScreeningService (Android 10+)

   • Official Android API for call screening
   • Requires being set as default Call Screening app
   • May not work on all custom ROMs

2. BroadcastReceiver Fallback

   • Listens for PHONE_STATE broadcasts
   • Uses TelecomManager.endCall() to reject calls
   • Works on most phones including custom ROMs

Action Behaviors

Action	Behavior	Notification
Block	Reject immediately	No notification
Silence	Mute ringer, call visible	User can answer/decline
Voicemail	Decline (routes to voicemail)	Missed call notification

Rule Priority

1. ALLOW rules are always checked first
2. If an ALLOW rule matches → call is allowed
3. BLOCK/SILENCE/VOICEMAIL rules are checked next
4. If a blocking rule matches → action is taken
5. If no rule matches → call is allowed (logged as "NOT MATCH")

Troubleshooting

Calls not being blocked

1. Check permissions: Ensure Phone and Call Logs permissions are granted
2. Check the pattern: Use the Call Log to see the raw number format
3. Check rule is enabled: Toggle switch should be ON (blue)
4. Try full number: Test with the exact phone number (no wildcards) first

Finding the right pattern

1. Let a call come through
2. Open 📋 Log to see the raw number
3. Create a pattern based on that format

App not appearing in Default Apps

Some phones hide the Call Screening option. The app's BroadcastReceiver fallback should still work.

Permission denied errors

Some phones require additional permissions. Go to:

• Settings → Apps → Phone Blocker → Permissions → Grant all available permissions

For Chinese ROMs (Xiaomi, OPPO, Vivo):

• Enable "Autostart" permission
• Disable battery optimization for the app

CI/CD

The project uses GitHub Actions for continuous integration:

• test.yml - Runs on push to main/dev and PRs

  • Runs unit tests
  • Runs Android lint
  • Builds APK

• release.yml - Runs on tag push (v*)

  • Builds debug and release APKs
  • Creates GitHub Release with APKs attached

To create a release:

git tag v0.0.3
git push origin v0.0.3

License

MIT License - Feel free to use and modify.

Contributing

Pull requests welcome! Please:

• Run tests before submitting: ./gradlew testDebugUnitTest
• Test on multiple devices if possible
• Update documentation for new features

Links

• GitHub: https://github.com/johnwmail/phone-blocker
• Live Preview: https://johnwmail.github.io/phone-blocker/preview.html
• Download: https://johnwmail.github.io/phone-blocker/
• Releases: https://github.com/johnwmail/phone-blocker/releases