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Basic Usage​

To use ReDex, first build your app and find the APK for it. Then the simplest invocation is:

[python3] path/to/your.apk -o path/to/output.apk

A more complete invocation with:

[python3] -c default.config \
--android-sdk-path path/to/android/sdk \
path/to/your.apk -o path/to/output.apk

The full set of options can be found with

[python3] --help

and at the time of writing is

usage: [-h] [-o [OUT]] [-j JARPATHS] [--redex-binary [REDEX_BINARY]]
[-c CONFIG] [--sign] [-s [KEYSTORE]] [-a [KEYALIAS]]
[-p [KEYPASS]] [-u] [--unpack-dest UNPACK_DEST] [-w [WARN]]
[-d] [--dev] [-m [PROGUARD_MAP]] [--printseeds [PRINTSEEDS]]
[--lldb] [--gdb] [--ignore-zipalign] [--verify-none-mode]
[--enable-instrument-pass] [--is-art-build] [--enable-pgi]
[--post-lowering] [--disable-dex-hasher] [--page-align-libs]
[--side-effect-summaries SIDE_EFFECT_SUMMARIES]
[--escape-summaries ESCAPE_SUMMARIES] [--stop-pass STOP_PASS]
[--output-ir OUTPUT_IR]
[--debug-source-root [DEBUG_SOURCE_ROOT]] [--always-clean-up]
[--cmd-prefix CMD_PREFIX] [--reset-zip-timestamps] [-q]
[--android-sdk-path ANDROID_SDK_PATH]

Given an APK, produce a better APK!

positional arguments:
input_apk Input APK file

optional arguments:
-h, --help show this help message and exit
-o [OUT], --out [OUT]
Output APK file name (defaults to redex-out.apk)
Path to dependent library jar file
--redex-binary [REDEX_BINARY]
Path to redex binary
-c CONFIG, --config CONFIG
Configuration file
--sign, --no-sign Sign the apk after optimizing it
-s [KEYSTORE], --keystore [KEYSTORE]
-a [KEYALIAS], --keyalias [KEYALIAS]
-p [KEYPASS], --keypass [KEYPASS]
-u, --unpack-only Unpack the apk and print the unpacked directories,
don't run any redex passes or repack the apk
--unpack-dest UNPACK_DEST
Specify the base name of the destination directories;
works with -u
-w [WARN], --warn [WARN]
Control verbosity of warnings
-d, --debug Unpack the apk and print the redex command line to run
--dev Optimize for development speed
-m [PROGUARD_MAP], --proguard-map [PROGUARD_MAP]
Path to proguard mapping.txt for deobfuscating names
--printseeds [PRINTSEEDS]
File to print seeds to
--used-js-assets USED_JS_ASSETS
A JSON file (or files) containing a list of resources
used by JS
Path to proguard config
-k [KEEP], --keep [KEEP]
[deprecated] Path to file containing classes to keep
-A [ARCH], --arch [ARCH]
Architecture; one of arm/armv7/arm64/x86_64/x86"
-S PASSTHRU Arguments passed through to redex
-J PASSTHRU_JSON JSON-formatted arguments passed through to redex
--lldb Run redex binary in lldb
--gdb Run redex binary in gdb
--ignore-zipalign Ignore if zipalign is not found
--verify-none-mode Enable verify-none mode on redex
Enable InstrumentPass if any
--is-art-build States that this is an art only build
--enable-pgi If not passed, Profile Guided Inlining is disabled
--post-lowering Specifies whether post lowering steps should be run
--disable-dex-hasher Disable DexHasher
--page-align-libs Preserve 4k page alignment for uncompressed libs
--side-effect-summaries SIDE_EFFECT_SUMMARIES
Side effect information for external methods
--escape-summaries ESCAPE_SUMMARIES
Escape information for external methods
--stop-pass STOP_PASS
Stop before a pass and dump intermediate dex and IR
meta data to a directory
--output-ir OUTPUT_IR
Stop before stop_pass and dump intermediate dex and IR
meta data to output_ir folder
--debug-source-root [DEBUG_SOURCE_ROOT]
Root directory that all references to source files in
debug information is given relative to.
--always-clean-up Clean up temporaries even under failure
--cmd-prefix CMD_PREFIX
Prefix redex-all with
Reset zip timestamps for deterministic output
-q, --quiet Do not be verbose, and override TRACE.
--android-sdk-path ANDROID_SDK_PATH
Path to Android SDK

From here, you may want to read the configuration guide and details about the passes.

The result output.apk should be smaller and faster than the input.


If you want some statistics about each pass, you can turn on tracing:

export TRACE=1

More specifically, tracing has categories and levels. For a TRACE(X, Y, msg) statement in the code to be logged, category X must have level Y or higher:

export TRACE=X:1,Y:2,Z:3

The output of tracing can also be redirected to a file with the TRACEFILE variable:

export TRACEFILE=/path/to/trace.txt