diff --git a/Makefile b/Makefile
index 3989a176a8..5f6ff11128 100644
--- a/Makefile
+++ b/Makefile
@@ -178,9 +178,12 @@ native: $(OUTDIR)/Makefile.native
 $(ANDROID_ARCHES): $(addprefix $$@.,$(MODES))
 
 $(ANDROID_BUILDS): $(GYPFILES) $(ENVFILE) build/android.gypi \
-                   must-set-ANDROID_NDK_ROOT
-	@tools/android-build.sh $(basename $@) $(subst .,,$(suffix $@)) \
-	                        $(OUTDIR) $(GYPFLAGS)
+                   must-set-ANDROID_NDK_ROOT Makefile.android
+	@$(MAKE) -f Makefile.android $@ \
+	        ARCH="$(basename $@)" \
+	        MODE="$(subst .,,$(suffix $@))" \
+	        OUTDIR="$(OUTDIR)" \
+	        GYPFLAGS="$(GYPFLAGS)"
 
 # Test targets.
 check: all
@@ -231,8 +234,8 @@ native.clean:
 clean: $(addsuffix .clean, $(ARCHES) $(ANDROID_ARCHES)) native.clean
 
 # GYP file generation targets.
-MAKEFILES = $(addprefix $(OUTDIR)/Makefile.,$(ARCHES))
-$(MAKEFILES): $(GYPFILES) $(ENVFILE)
+OUT_MAKEFILES = $(addprefix $(OUTDIR)/Makefile.,$(ARCHES))
+$(OUT_MAKEFILES): $(GYPFILES) $(ENVFILE)
 	GYP_GENERATORS=make \
 	build/gyp/gyp --generator-output="$(OUTDIR)" build/all.gyp \
 	              -Ibuild/standalone.gypi --depth=. \
diff --git a/Makefile.android b/Makefile.android
new file mode 100644
index 0000000000..bdbcbb4ef1
--- /dev/null
+++ b/Makefile.android
@@ -0,0 +1,92 @@
+# Copyright 2012 the V8 project authors. All rights reserved.
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+#       copyright notice, this list of conditions and the following
+#       disclaimer in the documentation and/or other materials provided
+#       with the distribution.
+#     * Neither the name of Google Inc. nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+# Those definitions should be consistent with the main Makefile
+ANDROID_ARCHES = android_ia32 android_arm
+MODES = release debug
+
+# Generates all combinations of ANDROID ARCHES and MODES,
+# e.g. "android_ia32.release" or "android_arm.release"
+ANDROID_BUILDS = $(foreach mode,$(MODES), \
+                   $(addsuffix .$(mode),$(ANDROID_ARCHES)))
+
+HOST_OS = $(shell uname -s | sed -e 's/Linux/linux/;s/Darwin/mac/')
+ifeq ($(HOST_OS), linux)
+  TOOLCHAIN_DIR = linux-x86
+else
+  ifeq ($(HOST_OS), mac)
+    TOOLCHAIN_DIR = darwin-x86
+  else
+    $(error Host platform "${HOST_OS}" is not supported)
+  endif
+endif
+
+ifeq ($(ARCH), android_arm)
+  DEFINES  = target_arch=arm v8_target_arch=arm android_target_arch=arm
+  DEFINES += arm_neon=0 armv7=1
+  TOOLCHAIN_ARCH = arm-linux-androideabi-4.4.3
+else
+  ifeq ($(ARCH), android_ia32)
+    DEFINES = target_arch=ia32 v8_target_arch=ia32 android_target_arch=x86
+    TOOLCHAIN_ARCH = x86-4.4.3
+  else
+    $(error Target architecture "${ARCH}" is not supported)
+  endif
+endif
+
+TOOLCHAIN_PATH = ${ANDROID_NDK_ROOT}/toolchains/${TOOLCHAIN_ARCH}/prebuilt
+ANDROID_TOOLCHAIN = ${TOOLCHAIN_PATH}/${TOOLCHAIN_DIR}/bin
+ifeq ($(wildcard $(ANDROID_TOOLCHAIN)),)
+  $(error Cannot find Android toolchain in "${ANDROID_TOOLCHAIN}")
+endif
+
+# For mksnapshot host generation.
+DEFINES += host_os=${HOST_OS}
+
+.SECONDEXPANSION:
+$(ANDROID_BUILDS): $(OUTDIR)/Makefile.$$(basename $$@)
+	@$(MAKE) -C "$(OUTDIR)" -f Makefile.$(basename $@) \
+	            CXX="$(ANDROID_TOOLCHAIN)/*-g++" \
+	            AR="$(ANDROID_TOOLCHAIN)/*-ar" \
+	            RANLIB="$(ANDROID_TOOLCHAIN)/*-ranlib" \
+	            CC="$(ANDROID_TOOLCHAIN)/*-gcc" \
+	            LD="$(ANDROID_TOOLCHAIN)/*-ld" \
+	            LINK="$(ANDROID_TOOLCHAIN)/*-g++" \
+	            BUILDTYPE=$(shell echo $(subst .,,$(suffix $@)) | \
+	                        python -c "print raw_input().capitalize()") \
+	            builddir="$(shell pwd)/$(OUTDIR)/$@"
+
+# Android GYP file generation targets.
+ANDROID_MAKEFILES = $(addprefix $(OUTDIR)/Makefile.,$(ANDROID_ARCHES))
+$(ANDROID_MAKEFILES):
+	@GYP_GENERATORS=make-android \
+	GYP_DEFINES="${DEFINES}" \
+	CC="${ANDROID_TOOLCHAIN}/*-gcc" \
+	CXX="${ANDROID_TOOLCHAIN}/*-g++" \
+	build/gyp/gyp --generator-output="${OUTDIR}" build/all.gyp \
+	              -Ibuild/standalone.gypi --depth=. -Ibuild/android.gypi \
+	              -S.${ARCH} ${GYPFLAGS}
diff --git a/tools/android-build.sh b/tools/android-build.sh
index e5af59050b..e69de29bb2 100755
--- a/tools/android-build.sh
+++ b/tools/android-build.sh
@@ -1,97 +0,0 @@
-#!/bin/bash
-# Copyright 2012 the V8 project authors. All rights reserved.
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met:
-#
-#     * Redistributions of source code must retain the above copyright
-#       notice, this list of conditions and the following disclaimer.
-#     * Redistributions in binary form must reproduce the above
-#       copyright notice, this list of conditions and the following
-#       disclaimer in the documentation and/or other materials provided
-#       with the distribution.
-#     * Neither the name of Google Inc. nor the names of its
-#       contributors may be used to endorse or promote products derived
-#       from this software without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-if [ ${#@} -lt 4 ] ; then
-  echo "$0: Error: needs 4 arguments."
-  exit 1
-fi
-
-ARCH=$1
-MODE=$2
-OUTDIR=$3
-GYPFLAGS=$4
-
-host_os=$(uname -s | sed -e 's/Linux/linux/;s/Darwin/mac/')
-
-case "${host_os}" in
-  "linux")
-    toolchain_dir="linux-x86"
-    ;;
-  "mac")
-    toolchain_dir="darwin-x86"
-    ;;
-  *)
-    echo "$0: Host platform ${host_os} is not supported" >& 2
-    exit 1
-esac
-
-case "${ARCH}" in
-  "android_arm")
-    DEFINES=" target_arch=arm v8_target_arch=arm android_target_arch=arm"
-    DEFINES+=" arm_neon=0 armv7=1"
-    toolchain_arch="arm-linux-androideabi-4.4.3"
-    ;;
-  "android_ia32")
-    DEFINES=" target_arch=ia32 v8_target_arch=ia32 android_target_arch=x86"
-    toolchain_arch="x86-4.4.3"
-    ;;
-  *)
-    echo "$0: Target architecture ${ARCH} is not supported." >& 2
-    echo "$0: Current supported architectures: android_arm|android_ia32." >& 2
-    exit 1
-esac
-
-toolchain_path="${ANDROID_NDK_ROOT}/toolchains/${toolchain_arch}/prebuilt/"
-ANDROID_TOOLCHAIN="${toolchain_path}/${toolchain_dir}/bin"
-if [ ! -d "${ANDROID_TOOLCHAIN}" ]; then
-  echo "$0: Cannot find Android toolchain in ${ANDROID_TOOLCHAIN}." >& 2
-  echo "$0: The NDK version might be wrong." >& 2
-  exit 1
-fi
-
-# For mksnapshot host generation.
-DEFINES+=" host_os=${host_os}"
-
-# The set of GYP_DEFINES to pass to gyp.
-export GYP_DEFINES="${DEFINES}"
-
-# Use the "android" flavor of the Makefile generator for both Linux and OS X.
-export GYP_GENERATORS=make-android
-export CC=${ANDROID_TOOLCHAIN}/*-gcc
-export CXX=${ANDROID_TOOLCHAIN}/*-g++
-build/gyp/gyp --generator-output="${OUTDIR}" build/all.gyp \
-              -Ibuild/standalone.gypi --depth=. -Ibuild/android.gypi \
-              -S.${ARCH} ${GYPFLAGS}
-
-export AR=${ANDROID_TOOLCHAIN}/*-ar
-export RANLIB=${ANDROID_TOOLCHAIN}/*-ranlib
-export LD=${ANDROID_TOOLCHAIN}/*-ld
-export LINK=${ANDROID_TOOLCHAIN}/*-g++
-export BUILDTYPE=$(echo ${MODE} | python -c "print raw_input().capitalize()")
-export builddir=${PWD}/${OUTDIR}/${ARCH}.${MODE}
-make -C "${OUTDIR}" -f Makefile.${ARCH}