Smali Helper Plus

The modern, offline Smali & Dalvik bytecode reference for Android developers.

Every Dalvik opcode explained with real examples, a 28-lesson academy, a validating Smali editor and a full developer toolbox, in a Material 3 app built with Kotlin and Jetpack Compose. Made for Android reverse engineering, reading apktool / baksmali output, and learning how DEX bytecode really works.

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Download

Grab the latest signed APK from Releases (Smali-Helper-Plus-v<version>.apk, with a .sha256 checksum). A new version is published automatically after every successful push to main, and updates install over the previous version.

Requirements: Android 8.0 (API 26) or newer. No root, no account, works fully offline.

Why Smali Helper Plus?

Smali Helper Plus is a modern take on Zylern's original Smali Helper: the same idea, a pocket opcode reference grouped by category, rebuilt from scratch with verified documentation, a premium Material You interface and many new tools. No code or text from the original was reused.

	Original Smali Helper	Smali Helper Plus
Opcode reference	One screen per opcode	227 entries (all 224 instructions + 3 payloads) in 19 categories, verified against the official AOSP docs
Per opcode	Short description	Syntax, format, operands, explanation, technical details, example, Java/Kotlin equivalent, register usage, API level, common mistakes, related opcodes, official references
Search		Instant, typo-tolerant (invok-static → invoke-static), searches formats, examples and descriptions
Learning	Info pages	28 lessons, quizzes, flashcards, daily practice, streaks and achievements
Editor		Smali Playground with highlighting, live diagnostics, formatter, autocomplete, find & replace
Tools		13 developer tools (register calculator, converters, explainer, control flow, diff, ...)
Design	Classic views	Material 3, dynamic color, light/dark, edge-to-edge, tablet layouts

Screenshots

Home: opcode of the day, continue learning, stats	Opcodes: Smali basics and 19 categories	Opcode detail: format, operands, API level
Examples: highlighted Smali + Java equivalent	Search: typo-tolerant with highlights	Learn: lessons, daily practice, flashcards
Lessons: Smali next to Java	Quizzes: instant feedback and explanations	Playground: editor with live diagnostics
Explainer: step-by-step + pseudocode	Tools: 13 developer utilities	Register calculator: p↔v mapping, wide pairs

Light theme and Material You dynamic color

Home (light)

Opcode detail (light)

Playground (light)

Dynamic color from wallpaper

All screenshots were taken on a Google Pixel 6 (Android 17).

Features

Opcode reference (the core)

• All 224 Dalvik instructions + 3 data payloads, generated from and cross-checked against the official Dalvik bytecode and instruction formats pages. Every example assembles with the real smali assembler.
• 19 categories: move, return, constants, monitors, type checks, objects, arrays, fields, invoke, arithmetic, bitwise, comparison, branches, jumps, switches, conversions, exceptions, method handles, advanced.
• Each opcode: value, format, syntax, operands with bit widths, explanation, technical description, real example, Java and Kotlin equivalents, register usage, minimum API / DEX version, common mistakes, related opcodes and official references. Copy, bookmark and share buttons.
• "Smali basics" shortcuts (what Smali is, registers, types, method signatures, debugging), like the info pages of the original app.

Search

Instant offline search over names, categories, formats (35c), syntax, descriptions and example code, with typo tolerance, suggestions and "did you mean", filters (category, format, min API, wide, range), highlighted matches and recent searches.

Learning academy

28 original lessons from "What is Smali?" to DEX structure, instruction encoding, annotations and reading obfuscated code, each with code examples, Java comparisons, exercises (open in the Playground) and a quiz. Also 141 quiz questions, 84 flashcards with spaced repetition, daily practice, streaks, a 12-week activity heatmap and 13 achievements. All progress is stored locally.

Smali Playground

A real editor: syntax highlighting, line numbers, auto-indent, undo/redo, find & replace, opcode autocomplete, register and bracket highlighting, live diagnostics (unknown opcodes, register limits per format, literal ranges, undefined labels, return-type mismatches, ...), a formatter, a method outline, editor themes and font sizes, snippet saving, and .smali open/save through the system file picker. Code is only parsed and validated, never compiled or executed.

Developer tools

Register calculator · number converter (dec/hex/bin/oct, signed/unsigned, float bits, "which const fits") · descriptor converter (java.lang.String ↔ Ljava/lang/String;, method signatures) · method explorer · control-flow viewer · Smali explainer with educational Java-style pseudocode · register usage visualizer · code comparison (diff) · API compatibility checker · instruction format explorer · cheat sheets · snippet library (77 snippets + your own collections).

And more

Bookmarks and history, backup and restore (JSON via the file picker), documentation updates without an app update (validated JSON, HTTPS only, atomic install, never code), and an optional bring-your-own-key AI assistant that asks before sending any code. Material 3 with dynamic color, light/dark themes, edge-to-edge, predictive back, adaptive phone/tablet layouts and large-font support.

Versioning and automatic releases

Versions are fully automatic; nobody edits version numbers by hand:

Value	Formula	Example
versionCode	number of commits	1, 2, 3, ...
versionName	<major>.<minor>.<commits - 1> (major/minor in version.properties)	1.0.0, 1.0.1, 1.0.2, ...
Release tag	v<versionName>	v1.0.2

push to main ──► Android CI (lint · unit tests · debug APK · Pixel 6 emulator tests)
                      │ success
                      ▼
                 Release workflow ──► builds + signs release APK ──► GitHub Release v1.0.N
                                                                    (APK · SHA-256 · build-info · changelog)

Pushes to other branches and pull requests are built and tested but never released. Signing uses four repository secrets; see Setup. Run ./gradlew printVersion to see the version locally, and bump minor/major in version.properties to start a new line (for example 1.1.0).

Setup for maintainers

Debug builds, tests and CI need no configuration. Automatic releases need four repository secrets. Add them under Settings → Secrets and variables → Actions → New repository secret:

Secret	What to put in it
ANDROID_KEYSTORE_BASE64	Your release keystore, base64 on one line: base64 -w0 release.jks
ANDROID_KEYSTORE_PASSWORD	The keystore password
ANDROID_KEY_ALIAS	The key alias you chose
ANDROID_KEY_PASSWORD	The key password

Create the keystore once, on your own machine, and back it up (losing it means you can no longer ship updates):

keytool -genkeypair -v -keystore release.jks -keyalg RSA -keysize 4096 -validity 10000 -alias smalihelper

No other secrets, variables, .env files or tokens are needed: publishing uses the built-in GITHUB_TOKEN, the AI key is entered by each user inside the app, and documentation updates come from this public repository. Step-by-step details: SECRETS_SETUP.md and CI_SETUP.md.

Build from source

Requirements: JDK 21, Android SDK platform android-37.0 and build-tools 37.0.0. The Gradle wrapper (9.8.2) downloads Gradle itself.

export JAVA_HOME=/usr/lib/jvm/java-21-openjdk     # any JDK 21
./gradlew clean
./gradlew lintDebug
./gradlew testDebugUnitTest                       # 438 JVM unit tests
./gradlew assembleDebug                           # app/build/outputs/apk/debug/app-debug.apk
./gradlew connectedDebugAndroidTest               # 60 Compose UI tests, needs a device or emulator

A local ./gradlew assembleRelease is unsigned unless the signing environment variables are set (see SECRETS_SETUP.md).

Testing

• 438 JVM unit tests: the Smali lexer/parser/validator/formatter, search engine, converters, learning logic, content validation, update pipeline, backup and AI client.
• 60 instrumented Compose UI tests: navigation, opcode reference, search, lessons and quizzes, Playground, tools, settings and Room. They pass on a physical Google Pixel 6 (Android 17) and run on a Pixel 6 emulator profile in CI.
• docs/TESTING.md has the Pixel 6 device matrix (cold start, dynamic color, light/dark, gesture and 3-button navigation, font scale, rotation, offline, process death) with the adb commands. scripts/pixel6-local-test.sh automates it for a connected device.
• Before pushing: scripts/check-secrets.sh scans the tree for committed secrets.

Architecture

Single module :app, MVVM with unidirectional data flow and Clean Architecture layering. Compose screens observe StateFlows from @HiltViewModels with collectAsStateWithLifecycle().

flowchart LR
    UI["Compose screens<br/>(feature/*)"] -->|events| VM["ViewModels<br/>StateFlow"]
    VM -->|state| UI
    VM --> Domain["domain<br/>(search, learning, tools)"]
    VM --> Repo["Repositories (data/*)"]
    Repo --> Room[("Room<br/>content + user data")]
    Repo --> DS[("DataStore<br/>preferences")]
    Repo --> Net["OkHttp<br/>updates / optional AI"]
    Net -.->|HTTPS only, validated JSON| Remote["content/manifest.json<br/>in this repository"]
    Work["WorkManager<br/>update checks"] --> Repo
    Seeder["Bundled content seeder<br/>assets/content/*.json"] --> Room
    Engine["core/smali<br/>lexer · parser · validator · formatter · CFG"] --> VM

Loading

Kotlin 2.4 · Jetpack Compose (BOM 2026.09) · Material 3 · Hilt · Room · DataStore · WorkManager · Navigation Compose (type-safe routes) · kotlinx.serialization · OkHttp. Exact versions and sources: VERSIONS.md.

app/src/main/java/com/riyadm/smalihelperplus/
├── core/
│   ├── smali/           Smali engine: lexer, parser, validator, formatter, explainer, register & control-flow analysis
│   ├── content/         content DTOs, validator, atomic installer, bundled content seeder
│   ├── database/        Room database, entities, DAOs (FTS4 opcode index)
│   ├── datastore/       user preferences
│   ├── designsystem/    theme, code colors, shared components (CodeBlock, EmptyState, ...)
│   ├── common/ di/      code hand-off between screens, Hilt modules
├── data/                repositories: opcode, learning, snippets, library, updates, backup, ai
├── domain/              pure logic: search engine, learning (streaks, Leitner, achievements), tools
├── feature/             home · opcodes · search · learn · playground · explainer · analysis · tools · snippets ·
│                        library · settings · updates · about · ai
└── navigation/          type-safe routes, NavHost, adaptive navigation suite

Content lives in app/src/main/assets/content/ (opcodes, lessons, snippets). The generators and the verification tooling (which assembles every example with real smali) are in tools/content-gen/.

Privacy and responsible use

• No analytics, no ads, no tracking. The only network uses are the optional documentation update check and the optional AI assistant you configure yourself. Code and keys are never logged.
• The AI key is stored with the Android Keystore and excluded from backups. Nothing is sent before you configure the assistant, and the app always asks before sending code.
• Smali Helper Plus is for learning and for analysing software you wrote or are authorised to inspect. Do not use it to bypass licensing, payments or other protections. The app never executes the code you paste or import and needs no root.

Documentation

File	Content
CI_SETUP.md	CI jobs, automatic versioning and releases, artifacts, emulator details
SECRETS_SETUP.md	Release signing secrets and keystore handling
VERSIONS.md	Pinned versions, official sources, verification date
docs/TESTING.md	Test levels and the Pixel 6 device matrix
content/README.md	Documentation update format
NOTICE.md	Third-party attribution

License

Copyright 2026 riyadmondol2006. Licensed under the Apache License, Version 2.0. Third-party notices are in NOTICE.md. Inspired by Smali Helper by Zylern. "Android" and "Pixel" are trademarks of Google LLC; this project is not affiliated with Google.