diff --git a/tools/android-sdk-25.0.2/apksigner b/tools/android-sdk-25.0.2/apksigner
deleted file mode 100644
index 11a7529..0000000
--- a/tools/android-sdk-25.0.2/apksigner
+++ /dev/null
@@ -1,89 +0,0 @@
-#!/bin/bash
-#
-# Copyright (C) 2016 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-# Set up prog to be the path of this script, including following symlinks,
-# and set up progdir to be the fully-qualified pathname of its directory.
-prog="$0"
-while [ -h "${prog}" ]; do
-    newProg=`/bin/ls -ld "${prog}"`
-    newProg=`expr "${newProg}" : ".* -> \(.*\)$"`
-    if expr "x${newProg}" : 'x/' >/dev/null; then
-        prog="${newProg}"
-    else
-        progdir=`dirname "${prog}"`
-        prog="${progdir}/${newProg}"
-    fi
-done
-oldwd=`pwd`
-progdir=`dirname "${prog}"`
-cd "${progdir}"
-progdir=`pwd`
-prog="${progdir}"/`basename "${prog}"`
-cd "${oldwd}"
-
-jarfile=apksigner.jar
-libdir="$progdir"
-
-if [ ! -r "$libdir/$jarfile" ]; then
-    # set apksigner.jar location for the SDK case
-    libdir="$libdir/lib"
-fi
-
-
-if [ ! -r "$libdir/$jarfile" ]; then
-    # set apksigner.jar location for the Android tree case
-    libdir=`dirname "$progdir"`/framework
-fi
-
-if [ ! -r "$libdir/$jarfile" ]; then
-    echo `basename "$prog"`": can't find $jarfile"
-    exit 1
-fi
-
-# By default, give apksigner a max heap size of 1 gig. This can be overridden
-# by using a "-J" option (see below).
-defaultMx="-Xmx1024M"
-
-# The following will extract any initial parameters of the form
-# "-J<stuff>" from the command line and pass them to the Java
-# invocation (instead of to apksigner). This makes it possible for you to add
-# a command-line parameter such as "-JXmx256M" in your scripts, for
-# example. "java" (with no args) and "java -X" give a summary of
-# available options.
-
-javaOpts=""
-
-while expr "x$1" : 'x-J' >/dev/null; do
-    opt=`expr "x$1" : 'x-J\(.*\)'`
-    javaOpts="${javaOpts} -${opt}"
-    if expr "x${opt}" : "xXmx[0-9]" >/dev/null; then
-        defaultMx="no"
-    fi
-    shift
-done
-
-if [ "${defaultMx}" != "no" ]; then
-    javaOpts="${javaOpts} ${defaultMx}"
-fi
-
-if [ "$OSTYPE" = "cygwin" ]; then
-    # For Cygwin, convert the jarfile path into native Windows style.
-    jarpath=`cygpath -w "$libdir/$jarfile"`
-else
-    jarpath="$libdir/$jarfile"
-fi
-
-exec java $javaOpts -jar "$jarpath" "$@"