diff --git a/AppAnalysis/preprocess/IntelliDroidPreprocessAPK.sh b/AppAnalysis/preprocess/IntelliDroidPreprocessAPK.sh
index ebbe1f5..3b35b35 100644
--- a/AppAnalysis/preprocess/IntelliDroidPreprocessAPK.sh
+++ b/AppAnalysis/preprocess/IntelliDroidPreprocessAPK.sh
@@ -6,7 +6,7 @@ if [ "$(uname)" == "Darwin" ]; then
     DARE=$(dirname $0)/dare-1.1.0-macos/dare
 fi
 
-APKTOOL=$(dirname $0)/apktool-2.0.0rc4/apktool
+APKTOOL=$(dirname $0)/apktool-2.3.1/apktool
 
 preprocessAPK() {
     # Expand the APK file path (only works in Linux)
diff --git a/AppAnalysis/preprocess/apktool-2.0.0rc4/apktool.jar b/AppAnalysis/preprocess/apktool-2.0.0rc4/apktool.jar
deleted file mode 100755
index a70a5d2..0000000
Binary files a/AppAnalysis/preprocess/apktool-2.0.0rc4/apktool.jar and /dev/null differ
diff --git a/AppAnalysis/preprocess/apktool-2.0.0rc4/LICENSE b/AppAnalysis/preprocess/apktool-2.3.1/LICENSE
similarity index 100%
rename from AppAnalysis/preprocess/apktool-2.0.0rc4/LICENSE
rename to AppAnalysis/preprocess/apktool-2.3.1/LICENSE
diff --git a/AppAnalysis/preprocess/apktool-2.0.0rc4/apktool b/AppAnalysis/preprocess/apktool-2.3.1/apktool
similarity index 100%
rename from AppAnalysis/preprocess/apktool-2.0.0rc4/apktool
rename to AppAnalysis/preprocess/apktool-2.3.1/apktool
diff --git a/AppAnalysis/preprocess/apktool-2.3.1/apktool.jar b/AppAnalysis/preprocess/apktool-2.3.1/apktool.jar
new file mode 100644
index 0000000..bd60488
Binary files /dev/null and b/AppAnalysis/preprocess/apktool-2.3.1/apktool.jar differ