Decompiler — APK Toolkit GUI

A single-window Tkinter app that bundles the everyday Android app-analysis workflow: decompile/recompile/sign APKs, manage a Frida server, run Frida scripts from a reusable library, inspect SharedPreferences, and spoof typed pref values — all without re-typing setup every day.

Authorized use only. This is a security-testing tool intended for analyzing apps you own or are explicitly authorized to test. The bundled Frida scripts (root/SSL/RAM bypasses, billing spoof-resistance check, pref spoofing) are for verifying your own apps' hardening. Don't use it against apps or services you don't have permission to test.

Features

Decompile / Recompile + Sign

• Decompile an APK with apktool into a named folder
• Split-APK aware: Play / App Bundle apps (a base.apk + split_config.* parts, or an .xapk/.apkm/.apks bundle) are auto-merged into one complete APK via APKEditor before decompiling, so native libraries (lib/<abi>/*.so) and split resources are included — no more dlopen failed: library "libXxx.so" not found after recompiling
• Rebuild → zipalign → apksigner sign → verify, in one click
• Auto-detects apktool, zipalign, apksigner from PATH / Android build-tools

Generic, zero-config tool discovery

• Finds every external tool (apktool, zipalign, apksigner, adb, java, APKEditor, frida/frida-ps) automatically — no machine-specific paths baked in (APKEditor.jar ships in tools/; java is found via PATH / JAVA_HOME / Android Studio's bundled JRE)
• Looks in: saved overrides → system PATH → Android SDK (build-tools, platform-tools, picked up from ANDROID_HOME/ANDROID_SDK_ROOT or the standard Studio install on Windows/macOS/Linux) → common emulator installs (Nox / BlueStacks / LDPlayer / MEmu / Genymotion)
• If something can't be found, the app asks you to point it at the binary and remembers your choice (apk_tool_gui.tools.json, git-ignored)
• A ⚙ Tools button (top-right) lets you view, edit, browse or re-detect every tool path at any time

Frida / ADB

• ⚡ Quick start: connect → start frida-server → check, in one button
• Robust frida-server start/kill/status (detects truncated process names)
• Live status header (device + frida-server up/down)
• adb auto-detected from PATH, falling back to a Nox bin folder

Scripts library + Frida Script runner

• Manage a .js library (new/edit/import/delete) in a popup editor
• Run a script over USB (-q -t inf, stays attached, streams console.log)
• Auto-preload helper scripts (*bypass*.js + current-screen.js) before your script
• Inject a Script arg (JS global ARG) into a script at run time
• Pref spoof: build typed rules (string/boolean/int/long/float) in a table; they're injected into pref-spoof.js and hook SharedPreferences getters live

Prefs (static, no Frida)

• List / view / edit / delete /data/data/<pkg>/shared_prefs/*.xml over adb
• Saves back preserving the file's owner/permissions

Quality-of-life

• Every field is remembered between launches (apk_tool_gui.config.json, git-ignored)
• No flashing cmd windows; all subprocess output streams into the app

Configuration

All tunable defaults live in one hand-editable, committed file: settings.ini (next to apk_tool_gui.py). It's a plain INI file — edit it to change behaviour, no code changes needed. Windows paths can be pasted exactly as-is (no escaping, no slash-flipping). Any missing or invalid key silently falls back to a built-in default, so you can keep only what you change (or delete the file to regenerate it).

Section / key	What it controls
[ui] title / geometry / min_width / min_height	Window title and sizing
[adb] default_host	Prefilled ADB device (host:port)
[adb] frida_remote	Default on-device frida-server path
[adb] prefer	Which adb to auto-pick first: emulator (Nox/BlueStacks/… — default, matches the emulator and avoids version conflicts) or sdk
[keystore] auto_detect_globs	Patterns used to auto-fill the keystore field
[tools.path] <tool>	Exact full path to a tool's binary — pin it explicitly (wins over everything); leave blank to auto-detect
[tools.names] <tool>	Executable filenames searched for each tool when its path is blank
[search_paths] android_sdk_roots	Extra Android SDK roots to scan
[search_paths] build_tools_dirs	Extra dirs holding zipalign / apksigner
[search_paths] platform_tools_dirs	Extra dirs holding adb
[search_paths] emulator_dirs	Extra emulator bin folders
[search_paths] extra_tool_dirs	Generic extra dirs searched for every tool

Example — pin adb to your emulator's binary. Just paste the path:

[tools.path]
adb = D:\Program Files\Nox\bin\adb.exe

Lists (names, search_paths, auto_detect_globs) can be comma-separated or one item per line.

The app also keeps two machine-specific, git-ignored files it manages for you (no need to edit by hand):

• apk_tool_gui.config.json — remembers your field values between launches
• apk_tool_gui.tools.json — remembers tool paths you picked in ⚙ Tools

Seeded scripts

On first run the app writes starter scripts into scripts/ (git-ignored, regenerated):

Script	Purpose
root-detection-bypass.js	Common root checks → not rooted
ssl-pinning-bypass.js	TrustManager / OkHttp3 pinning bypass
ram-check-bypass.js	Report high total RAM for "needs N GB" gates
current-screen.js	Log the current Activity / Fragment / Compose route / game host
pref-spoof.js	Return fake SharedPreferences values (driven by the GUI rule builder)
gpay-billing-spoof.js	Spoof-resistance test: fake a client-side purchase to confirm your app rejects it (server-side verification)
class-tracer.js	Trace every method of a class (ARG = class)
list-classes.js	List loaded classes matching a filter (ARG = filter)

Requirements

• Python 3 (uses stdlib tkinter)
• pip install -r requirements.txt (installs frida-tools; pin frida to your device's frida-server version)
• External tools (apktool, zipalign, apksigner, adb) — installed anywhere the app can discover them (PATH, Android SDK, or an emulator's bin folder). If they're somewhere unusual, just point the ⚙ Tools dialog at them once.

Run

python apk_tool_gui.py

or double-click APK Tool GUI.bat on Windows (launches with pythonw, no console).

Notes

• The ADB device field defaults to 127.0.0.1:62001 (a common emulator port) but works with any adb-reachable device/emulator — just edit the field.
• frida on the PC must match the frida-server version on the device.