bitchat for Android (github version) 1.3.1

bugfixes:
fix: tor startup
fix: deleting geohash bookmarks
fix: blocking geohash users
What's Changed
bump versioncode by
@callebtc
in
#419
lock to tor by
@callebtc
in
#426
fix: bookmark removal persistence by
@lollerfirst
in
#424
nostr: fix block feature by
@callebtc
in
#427
add github tests by
@callebtc
in
#233
better verbose logging by
@callebtc
in
#431
bump to 1.3.1 by
@callebtc
in
#432
Full Changelog
:
1.3.0...1.3.1

Warning

This software has not received external security review and may contain vulnerabilities and may not necessarily meet its stated security goals. Do not use it for sensitive use cases, and do not rely on its security until it has been reviewed. Work in progress.

bitchat for Android

A secure, decentralized, peer-to-peer messaging app that works over Bluetooth mesh networks. No internet required for mesh chats, no servers, no phone numbers - just pure encrypted communication. Bitchat also supports geohash channels, which use an internet connection to connect you with others in your geographic area.

This is the

Android port

of the original

bitchat iOS app

, maintaining 100% protocol compatibility for cross-platform communication.

Install bitchat

You can download the latest version of bitchat for Android from the

GitHub Releases page

.

Or you can:

Instructions:

Download the APK:

On your Android device, navigate to the link above and download the latest

.apk

file. Open it.

Allow Unknown Sources:

On some devices, before you can install the APK, you may need to enable "Install from unknown sources" in your device's settings. This is typically found under

Settings > Security

or

Settings > Apps & notifications > Special app access

.

Install:

Open the downloaded

.apk

file to begin the installation.

License

This project is released into the public domain. See the

LICENSE

file for details.

Features

✅ Cross-Platform Compatible

: Full protocol compatibility with iOS bitchat

✅ Decentralized Mesh Network

: Automatic peer discovery and multi-hop message relay over Bluetooth LE

✅ End-to-End Encryption

: X25519 key exchange + AES-256-GCM for private messages

✅ Channel-Based Chats

: Topic-based group messaging with optional password protection

✅ Store & Forward

: Messages cached for offline peers and delivered when they reconnect

✅ Privacy First

: No accounts, no phone numbers, no persistent identifiers

✅ IRC-Style Commands

: Familiar

/join

,

/msg

,

/who

style interface

✅ Message Retention

: Optional channel-wide message saving controlled by channel owners

✅ Emergency Wipe

: Triple-tap logo to instantly clear all data

✅ Modern Android UI

: Jetpack Compose with Material Design 3

✅ Dark/Light Themes

: Terminal-inspired aesthetic matching iOS version

✅ Battery Optimization

: Adaptive scanning and power management

Android Setup

Prerequisites

Android Studio

: Arctic Fox (2020.3.1) or newer

Android SDK

: API level 26 (Android 8.0) or higher

Kotlin

: 1.8.0 or newer

Gradle

: 7.0 or newer

Build Instructions

Clone the repository:

github.com/permissionlesstech/bitchat-android.git

cd bitchat-android">

git clone

github.com/permissionlesstech/bitchat-android.git

cd

bitchat-android

Open in Android Studio:

#

Open Android Studio and select "Open an Existing Project"

#

Navigate to the bitchat-android directory

Build the project:

./gradlew build

Install on device:

./gradlew installDebug

Development Build

For development builds with debugging enabled:

./gradlew assembleDebug adb install -r app/build/outputs/apk/debug/app-debug.apk

Release Build

For production releases:

./gradlew assembleRelease

Android-Specific Requirements

Permissions

The app requires the following permissions (automatically requested):

Bluetooth

: Core BLE functionality

Location

: Required for BLE scanning on Android

Notifications

: Message alerts and background updates

Hardware Requirements

Bluetooth LE (BLE)

: Required for mesh networking

Android 8.0+

: API level 26 minimum

RAM

: 2GB recommended for optimal performance

Usage

Basic Commands

/j #channel

- Join or create a channel

/m @name message

- Send a private message

/w

- List online users

/channels

- Show all discovered channels

/block @name

- Block a peer from messaging you

/block

- List all blocked peers

/unblock @name

- Unblock a peer

/clear

- Clear chat messages

/pass [password]

- Set/change channel password (owner only)

/transfer @name

- Transfer channel ownership

/save

- Toggle message retention for channel (owner only)

Getting Started

Install the app

on your Android device (requires Android 8.0+)

Grant permissions

for Bluetooth and location when prompted

Launch bitchat

- it will auto-start mesh networking

Set your nickname

or use the auto-generated one

Connect automatically

to nearby iOS and Android bitchat users

Join a channel

with

/j #general

or start chatting in public

Messages relay

through the mesh network to reach distant peers

Android UI Features

Jetpack Compose UI

: Modern Material Design 3 interface

Dark/Light Themes

: Terminal-inspired aesthetic matching iOS

Haptic Feedback

: Vibrations for interactions and notifications

Adaptive Layout

: Optimized for various Android screen sizes

Message Status

: Real-time delivery and read receipts

RSSI Indicators

: Signal strength colors for each peer

Channel Features

Password Protection

: Channel owners can set passwords with

/pass

Message Retention

: Owners can enable mandatory message saving with

/save

@ Mentions

: Use

@nickname

to mention users (with autocomplete)

Ownership Transfer

: Pass control to trusted users with

/transfer

Security & Privacy

Encryption

Private Messages

: X25519 key exchange + AES-256-GCM encryption

Channel Messages

: Argon2id password derivation + AES-256-GCM

Digital Signatures

: Ed25519 for message authenticity

Forward Secrecy

: New key pairs generated each session

Privacy Features

No Registration

: No accounts, emails, or phone numbers required

Ephemeral by Default

: Messages exist only in device memory

Cover Traffic

: Random delays and dummy messages prevent traffic analysis

Emergency Wipe

: Triple-tap logo to instantly clear all data

Bundled Tor Support

: Built-in Tor network integration for enhanced privacy when internet connectivity is available

Performance & Efficiency

Message Compression

LZ4 Compression

: Automatic compression for messages >100 bytes

30-70% bandwidth savings

on typical text messages

Smart compression

: Skips already-compressed data

Battery Optimization

Adaptive Power Modes

: Automatically adjusts based on battery level

Performance mode: Full features when charging or >60% battery

Balanced mode: Default operation (30-60% battery)

Power saver: Reduced scanning when <30% battery

Ultra-low power: Emergency mode when <10% battery

Background efficiency

: Automatic power saving when app backgrounded

Configurable scanning

: Duty cycle adapts to battery state

Network Efficiency

Optimized Bloom filters

: Faster duplicate detection with less memory

Message aggregation

: Batches small messages to reduce transmissions

Adaptive connection limits

: Adjusts peer connections based on power mode

Technical Architecture

Binary Protocol

bitchat uses an efficient binary protocol optimized for Bluetooth LE:

Compact packet format with 1-byte type field

TTL-based message routing (max 7 hops)

Automatic fragmentation for large messages

Message deduplication via unique IDs

Mesh Networking

Each device acts as both client and peripheral

Automatic peer discovery and connection management

Store-and-forward for offline message delivery

Adaptive duty cycling for battery optimization

Android-Specific Optimizations

Coroutine Architecture

: Asynchronous operations for mesh networking

Kotlin Coroutines

: Thread-safe concurrent mesh operations

EncryptedSharedPreferences

: Secure storage for user settings

Lifecycle-Aware

: Proper handling of Android app lifecycle

Battery Optimization

: Foreground service and adaptive scanning

Android Technical Architecture

Core Components

BitchatApplication.kt

: Application-level initialization and dependency injection

MainActivity.kt

: Main activity handling permissions and UI hosting

ChatViewModel.kt

: MVVM pattern managing app state and business logic

BluetoothMeshService.kt

: Core BLE mesh networking (central + peripheral roles)

EncryptionService.kt

: Cryptographic operations using BouncyCastle

BinaryProtocol.kt

: Binary packet encoding/decoding matching iOS format

ChatScreen.kt

: Jetpack Compose UI with Material Design 3

Dependencies

Jetpack Compose

: Modern declarative UI

BouncyCastle

: Cryptographic operations (X25519, Ed25519, AES-GCM)

Nordic BLE Library

: Reliable Bluetooth LE operations

Kotlin Coroutines

: Asynchronous programming

LZ4

: Message compression (when enabled)

EncryptedSharedPreferences

: Secure local storage

Binary Protocol Compatibility

The Android implementation maintains 100% binary protocol compatibility with iOS:

Header Format

: Identical 13-byte header structure

Packet Types

: Same message types and routing logic

Encryption

: Identical cryptographic algorithms and key exchange

UUIDs

: Same Bluetooth service and characteristic identifiers

Fragmentation

: Compatible message fragmentation for large content

Publishing to Google Play

Preparation

Update version information:

//

In app/build.gradle.kts

defaultConfig { versionCode

=

2

//

Increment for each release

versionName

=

"

1.1.0

"

//

User-visible version

}

Create a signed release build:

./gradlew assembleRelease

Generate app bundle (recommended for Play Store):

./gradlew bundleRelease

Play Store Requirements

Target API

: Latest Android API (currently 34)

Privacy Policy

: Required for apps requesting sensitive permissions

App Permissions

: Justify Bluetooth and location usage

Content Rating

: Complete questionnaire for age-appropriate content

Distribution

Google Play Store

: Main distribution channel

F-Droid

: For open-source distribution

Direct APK

: For testing and development

Cross-Platform Communication

This Android port enables seamless communication with the original iOS bitchat app:

iPhone ↔ Android

: Full bidirectional messaging

Mixed Groups

: iOS and Android users in same channels

Feature Parity

: All commands and encryption work across platforms

Protocol Sync

: Identical message format and routing behavior

iOS Version

: For iPhone/iPad users, get the original bitchat at

github.com/jackjackbits/bitchat

Contributing

Contributions are welcome! Key areas for enhancement:

Performance

: Battery optimization and connection reliability

UI/UX

: Additional Material Design 3 features

Security

: Enhanced cryptographic features

Testing

: Unit and integration test coverage

Documentation

: API documentation and development guides

Support & Issues

Bug Reports

:

Create an issue

with device info and logs

Feature Requests

:

Start a discussion

Security Issues

: Email security concerns privately

iOS Compatibility

: Cross-reference with

original iOS repo

For iOS-specific issues, please refer to the

original iOS bitchat repository

.