diff --git a/core/Makefile b/core/Makefile
index 9cb8c82..852a716 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -802,8 +802,7 @@
 # -----------------------------------------------------------------
 # host tools needed to build OTA packages
 
-.PHONY: otatools
-otatools: $(HOST_OUT_EXECUTABLES)/minigzip \
+OTATOOLS :=  $(HOST_OUT_EXECUTABLES)/minigzip \
 	  $(HOST_OUT_EXECUTABLES)/mkbootfs \
 	  $(HOST_OUT_EXECUTABLES)/mkbootimg \
 	  $(HOST_OUT_EXECUTABLES)/fs_config \
@@ -815,6 +814,9 @@
 	  $(HOST_OUT_JAVA_LIBRARIES)/dumpkey.jar \
 	  $(HOST_OUT_JAVA_LIBRARIES)/signapk.jar
 
+.PHONY: otatools
+otatools: $(OTATOOLS)
+
 # -----------------------------------------------------------------
 # A zip of the directories that map to the target filesystem.
 # This zip can be used to create an OTA package or filesystem image
@@ -966,7 +968,7 @@
 $(INTERNAL_OTA_PACKAGE_TARGET): scriptmode := $(TARGET_OTA_SCRIPT_MODE)
 endif
 
-$(INTERNAL_OTA_PACKAGE_TARGET): $(BUILT_TARGET_FILES_PACKAGE) otatools
+$(INTERNAL_OTA_PACKAGE_TARGET): $(BUILT_TARGET_FILES_PACKAGE) $(OTATOOLS)
 	@echo "Package OTA: $@"
 	$(hide) ./build/tools/releasetools/ota_from_target_files \
 	   -m $(scriptmode) \
@@ -1100,7 +1102,7 @@
 $(INTERNAL_UPDATE_PACKAGE_TARGET): extensions := $(TARGET_RELEASETOOLS_EXTENSIONS)
 endif
 
-$(INTERNAL_UPDATE_PACKAGE_TARGET): $(BUILT_TARGET_FILES_PACKAGE) otatools
+$(INTERNAL_UPDATE_PACKAGE_TARGET): $(BUILT_TARGET_FILES_PACKAGE) $(OTATOOLS)
 	@echo "Package: $@"
 	$(hide) ./build/tools/releasetools/img_from_target_files \
 	   -s $(extensions) \
diff --git a/core/base_rules.mk b/core/base_rules.mk
index 0ad797a..0d17c83 100644
--- a/core/base_rules.mk
+++ b/core/base_rules.mk
@@ -189,13 +189,15 @@
 aidl_preprocess_import :=
 LOCAL_SDK_VERSION:=$(strip $(LOCAL_SDK_VERSION))
 ifdef LOCAL_SDK_VERSION
-ifneq ($(LOCAL_SDK_VERSION),current)
-aidl_preprocess_import := -p$(TOPDIR)prebuilt/sdk/$(LOCAL_SDK_VERSION)/framework.aidl
+ifeq ($(LOCAL_SDK_VERSION),current)
+  aidl_preprocess_import := $(TARGET_OUT_COMMON_INTERMEDIATES)/framework.aidl
+else
+  aidl_preprocess_import := $(HISTORICAL_SDK_VERSIONS_ROOT)/$(LOCAL_SDK_VERSION)/framework.aidl
 endif # !current
 endif # LOCAL_SDK_VERSION
-$(aidl_java_sources): PRIVATE_AIDL_FLAGS := -b $(aidl_preprocess_import) -I$(LOCAL_PATH) -I$(LOCAL_PATH)/src $(addprefix -I,$(LOCAL_AIDL_INCLUDES))
+$(aidl_java_sources): PRIVATE_AIDL_FLAGS := -b $(addprefix -p,$(aidl_preprocess_import)) -I$(LOCAL_PATH) -I$(LOCAL_PATH)/src $(addprefix -I,$(LOCAL_AIDL_INCLUDES))
 
-$(aidl_java_sources): $(intermediates.COMMON)/src/%.java: $(TOPDIR)$(LOCAL_PATH)/%.aidl $(PRIVATE_ADDITIONAL_DEPENDENCIES) $(AIDL)
+$(aidl_java_sources): $(intermediates.COMMON)/src/%.java: $(TOPDIR)$(LOCAL_PATH)/%.aidl $(PRIVATE_ADDITIONAL_DEPENDENCIES) $(AIDL) $(aidl_preprocess_import)
 	$(transform-aidl-to-java)
 -include $(aidl_java_sources:%.java=%.P)
 
@@ -235,7 +237,8 @@
 ###########################################################
 #TODO: pull this into java.make once host and target are combined
 
-java_sources := $(addprefix $(TOP_DIR)$(LOCAL_PATH)/, $(filter %.java,$(LOCAL_SRC_FILES))) $(aidl_java_sources) $(logtags_java_sources)
+java_sources := $(addprefix $(TOP_DIR)$(LOCAL_PATH)/, $(filter %.java,$(LOCAL_SRC_FILES))) $(aidl_java_sources) $(logtags_java_sources) \
+                $(filter %.java,$(LOCAL_GENERATED_SOURCES))
 all_java_sources := $(java_sources) $(addprefix $($(my_prefix)OUT_COMMON_INTERMEDIATES)/, $(filter %.java,$(LOCAL_INTERMEDIATE_SOURCES)))
 
 ## Java resources #########################################
@@ -319,8 +322,14 @@
 ifeq ($(my_prefix),TARGET_)
 ifeq ($(LOCAL_SDK_VERSION),)
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_BOOTCLASSPATH := -bootclasspath $(call java-lib-files,core)
-endif
-endif
+else
+ifeq ($(LOCAL_SDK_VERSION),current)
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_BOOTCLASSPATH := -bootclasspath $(call java-lib-files,android_stubs_current)
+else
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_BOOTCLASSPATH := -bootclasspath $(call java-lib-files,sdk_v$(LOCAL_SDK_VERSION))
+endif # current
+endif # LOCAL_SDK_VERSION
+endif # TARGET_
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_RESOURCE_DIR := $(LOCAL_RESOURCE_DIR)
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_EXTRA_JAR_ARGS := $(extra_jar_args)
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_ASSET_DIR := $(LOCAL_ASSET_DIR)
@@ -482,6 +491,8 @@
 
 # Don't use += on subvars, or else they'll end up being
 # recursively expanded.
+ALL_MODULES.$(LOCAL_MODULE).CLASS := \
+    $(ALL_MODULES.$(LOCAL_MODULE).CLASS) $(LOCAL_MODULE_CLASS)
 ALL_MODULES.$(LOCAL_MODULE).PATH := \
     $(ALL_MODULES.$(LOCAL_MODULE).PATH) $(LOCAL_PATH)
 ALL_MODULES.$(LOCAL_MODULE).TAGS := \
diff --git a/core/config.mk b/core/config.mk
index a4d3154..2dcd876 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -314,22 +314,26 @@
 # For use with the LOCAL_SDK_VERSION variable for include $(BUILD_PACKAGE)
 # ###############################################################
 
-# The files that we can convert into android.jars are are in config/api/*.xml
-# The 'current' version is whatever this source tree is.  Once the apicheck
-# tool can generate the stubs from the xml files, we'll use that to be
-# able to build back-versions.  In the meantime, 'current' is the only
-# one supported.
+HISTORICAL_SDK_VERSIONS_ROOT := $(TOPDIR)prebuilt/sdk
+
+# Historical SDK version N is stored in $(HISTORICAL_SDK_VERSIONS_ROOT)/N.
+# The 'current' version is whatever this source tree is.
 #
 # sgrax     is the opposite of xargs.  It takes the list of args and puts them
 #           on each line for sort to process.
 # sort -g   is a numeric sort, so 1 2 3 10 instead of 1 10 2 3.
-TARGET_AVAILABLE_SDK_VERSIONS := current \
-        $(shell function sgrax() { \
-                while [ -n "$$1" ] ; do echo $$1 ; shift ; done \
-            } ; \
-            ( sgrax $(patsubst $(SRC_API_DIR)/%.xml,%, \
-                $(filter-out $(SRC_API_DIR)/current.xml, \
-                $(shell find $(SRC_API_DIR) -name "*.xml"))) | sort -g ) )
 
+# Numerically sort a list of numbers
+# $(1): the list of numbers to be sorted
+define numerically_sort
+$(shell function sgrax() { \
+    while [ -n "$$1" ] ; do echo $$1 ; shift ; done \
+    } ; \
+    ( sgrax $(1) | sort -g ) )
+endef
+
+TARGET_AVAILABLE_SDK_VERSIONS := current $(call numerically_sort,\
+    $(patsubst $(HISTORICAL_SDK_VERSIONS_ROOT)/%/android.jar,%, \
+    $(wildcard $(HISTORICAL_SDK_VERSIONS_ROOT)/*/android.jar)))
 
 INTERNAL_PLATFORM_API_FILE := $(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/public_api.xml
diff --git a/core/definitions.mk b/core/definitions.mk
index 5768c6d..2a771c2 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -1751,7 +1751,7 @@
 # clear_vars.mk.
 ###########################################################
 define inherit-package
-  $(eval $(call inherit-package-internal,$(1),$(2),$(3),$(4),$(5)))
+  $(eval $(call inherit-package-internal,$(1),$(2),$(3),$(4),$(5),$(6)))
 endef
 
 define inherit-package-internal
diff --git a/core/envsetup.mk b/core/envsetup.mk
index f8a2027..86aa2f3 100644
--- a/core/envsetup.mk
+++ b/core/envsetup.mk
@@ -342,6 +342,7 @@
 $(info   TARGET_BUILD_VARIANT=$(TARGET_BUILD_VARIANT))
 $(info   TARGET_SIMULATOR=$(TARGET_SIMULATOR))
 $(info   TARGET_BUILD_TYPE=$(TARGET_BUILD_TYPE))
+$(info   TARGET_BUILD_APPS=$(TARGET_BUILD_APPS))
 $(info   TARGET_ARCH=$(TARGET_ARCH))
 $(info   HOST_ARCH=$(HOST_ARCH))
 $(info   HOST_OS=$(HOST_OS))
diff --git a/core/main.mk b/core/main.mk
index f830f03..ae7abb6 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -46,6 +46,7 @@
 BUILD_SYSTEM := $(TOPDIR)build/core
 
 # This is the default target.  It must be the first declared target.
+.PHONY: droid
 DEFAULT_GOAL := droid
 $(DEFAULT_GOAL):
 
@@ -686,34 +687,60 @@
 	$(INSTALLED_USERDATAIMAGE_TARGET) \
 	$(INSTALLED_FILES_FILE)
 
-# The actual files built by the droidcore target changes depending
-# on the build variant.
+ifneq ($(TARGET_BUILD_APPS),)
+  # If this build is just for apps, only build apps and not the full system by default.
+
+  unbundled_build_modules :=
+  ifneq ($(filter all,$(TARGET_BUILD_APPS)),)
+    # If they used the magic goal "all" then build all apps in the source tree.
+    unbundled_build_modules := $(foreach m,$(sort $(ALL_MODULES)),$(if $(filter APPS,$(ALL_MODULES.$(m).CLASS)),$(m)))
+  else
+    unbundled_build_modules := $(TARGET_BUILD_APPS)
+  endif
+
+  # dist the unbundled app.
+  $(call dist-for-goals,apps_only, \
+    $(foreach m,$(unbundled_build_modules),$(ALL_MODULES.$(m).INSTALLED)) \
+  )
+
+.PHONY: apps_only
+apps_only: $(unbundled_build_modules)
+
+droid: apps_only
+
+else # TARGET_BUILD_APPS
+  $(call dist-for-goals, droidcore, \
+    $(INTERNAL_UPDATE_PACKAGE_TARGET) \
+    $(INTERNAL_OTA_PACKAGE_TARGET) \
+    $(SYMBOLS_ZIP) \
+    $(APPS_ZIP) \
+    $(INTERNAL_EMULATOR_PACKAGE_TARGET) \
+    $(PACKAGE_STATS_FILE) \
+    $(INSTALLED_FILES_FILE) \
+    $(INSTALLED_BUILD_PROP_TARGET) \
+    $(BUILT_TARGET_FILES_PACKAGE) \
+    $(INSTALLED_ANDROID_INFO_TXT_TARGET) \
+   )
+
+  # Tests are installed in userdata.img.  If we're building the tests
+  # variant, copy it for "make tests dist".  Also copy a zip of the
+  # contents of userdata.img, so that people can easily extract a
+  # single .apk.
+  ifeq ($(TARGET_BUILD_VARIANT),tests)
+  $(call dist-for-goals, droid, \
+    $(INSTALLED_USERDATAIMAGE_TARGET) \
+    $(BUILT_TESTS_ZIP_PACKAGE) \
+   )
+  endif
+
+# Building a full system-- the default is to build droidcore
+droid: droidcore
+
+endif # TARGET_BUILD_APPS
+
+
 .PHONY: droid tests
-droid tests: droidcore
-
-$(call dist-for-goals, droid, \
-	$(INTERNAL_UPDATE_PACKAGE_TARGET) \
-	$(INTERNAL_OTA_PACKAGE_TARGET) \
-	$(SYMBOLS_ZIP) \
-	$(APPS_ZIP) \
-	$(INTERNAL_EMULATOR_PACKAGE_TARGET) \
-	$(PACKAGE_STATS_FILE) \
-	$(INSTALLED_FILES_FILE) \
-	$(INSTALLED_BUILD_PROP_TARGET) \
-	$(BUILT_TARGET_FILES_PACKAGE) \
-	$(INSTALLED_ANDROID_INFO_TXT_TARGET) \
- )
-
-# Tests are installed in userdata.img.  If we're building the tests
-# variant, copy it for "make tests dist".  Also copy a zip of the
-# contents of userdata.img, so that people can easily extract a
-# single .apk.
-ifeq ($(TARGET_BUILD_VARIANT),tests)
-$(call dist-for-goals, droid, \
-	$(INSTALLED_USERDATAIMAGE_TARGET) \
-	$(BUILT_TESTS_ZIP_PACKAGE) \
- )
-endif
+tests: droidcore
 
 .PHONY: docs
 docs: $(ALL_DOCS)
diff --git a/core/package.mk b/core/package.mk
index 24807f9..cdeefb4 100644
--- a/core/package.mk
+++ b/core/package.mk
@@ -244,17 +244,24 @@
 # Most packages should link against the resources defined by framework-res.
 # Even if they don't have their own resources, they may use framework
 # resources.
+ifneq ($(filter-out current,$(LOCAL_SDK_VERSION)),)
+# for released sdk versions, the platform resources were built into android.jar.
+framework_res_package_export := \
+	$(HISTORICAL_SDK_VERSIONS_ROOT)/$(LOCAL_SDK_VERSION)/android.jar
+framework_res_package_export_deps := $(framework_res_package_export)
+else # LOCAL_SDK_VERSION
 framework_res_package_export := \
 	$(call intermediates-dir-for,APPS,framework-res,,COMMON)/package-export.apk
-$(LOCAL_INTERMEDIATE_TARGETS): \
-	PRIVATE_AAPT_INCLUDES := $(framework_res_package_export)
 # We can't depend directly on the export.apk file; it won't get its
 # PRIVATE_ vars set up correctly if we do.  Instead, depend on the
 # corresponding R.stamp file, which lists the export.apk as a dependency.
 framework_res_package_export_deps := \
 	$(dir $(framework_res_package_export))src/R.stamp
+endif # LOCAL_SDK_VERSION
 $(R_file_stamp): $(framework_res_package_export_deps)
-endif
+$(LOCAL_INTERMEDIATE_TARGETS): \
+	PRIVATE_AAPT_INCLUDES := $(framework_res_package_export)
+endif # LOCAL_NO_STANDARD_LIBRARIES
 
 ifneq ($(full_classes_jar),)
 $(LOCAL_BUILT_MODULE): PRIVATE_DEX_FILE := $(built_dex)
@@ -304,6 +311,10 @@
 # Define the rule to build the actual package.
 $(LOCAL_BUILT_MODULE): $(AAPT) | $(ZIPALIGN)
 $(LOCAL_BUILT_MODULE): PRIVATE_JNI_SHARED_LIBRARIES := $(jni_shared_libraries)
+ifneq ($(TARGET_BUILD_APPS),)
+    # Include all resources for unbundled apps.
+    $(LOCAL_BUILT_MODULE): PRODUCT_AAPT_CONFIG :=
+endif
 $(LOCAL_BUILT_MODULE): $(all_res_assets) $(jni_shared_libraries) $(full_android_manifest)
 	@echo "target Package: $(PRIVATE_MODULE) ($@)"
 	$(create-empty-package)
diff --git a/core/product.mk b/core/product.mk
index eca98ed..38d1148 100644
--- a/core/product.mk
+++ b/core/product.mk
@@ -29,13 +29,13 @@
 endef
 
 #
-# Returns the sorted concatenation of all PRODUCT_MAKEFILES
-# variables set in all AndroidProducts.mk files.
-# $(call ) isn't necessary.
+# Returns the sorted concatenation of PRODUCT_MAKEFILES
+# variables set in the given AndroidProducts.mk files.
+# $(1): the list of AndroidProducts.mk files.
 #
-define get-all-product-makefiles
+define get-product-makefiles
 $(sort \
-  $(foreach f,$(_find-android-products-files), \
+  $(foreach f,$(1), \
     $(eval PRODUCT_MAKEFILES :=) \
     $(eval LOCAL_DIR := $(patsubst %/,%,$(dir $(f)))) \
     $(eval include $(f)) \
@@ -47,6 +47,15 @@
 endef
 
 #
+# Returns the sorted concatenation of all PRODUCT_MAKEFILES
+# variables set in all AndroidProducts.mk files.
+# $(call ) isn't necessary.
+#
+define get-all-product-makefiles
+$(call get-product-makefiles,$(_find-android-products-files))
+endef
+
+#
 # Functions for including product makefiles
 #
 
diff --git a/core/product_config.mk b/core/product_config.mk
index ffb8d27..04f6ce1 100644
--- a/core/product_config.mk
+++ b/core/product_config.mk
@@ -149,6 +149,26 @@
 # else: Use the value set in the environment or buildspec.mk.
 
 # ---------------------------------------------------------------
+# Provide "APP-<appname>" targets, which lets you build
+# an unbundled app.
+#
+unbundled_goals := $(strip $(filter APP-%,$(MAKECMDGOALS)))
+ifdef unbundled_goals
+  ifneq ($(words $(unbundled_goals)),1)
+    $(error Only one APP-* goal may be specified; saw "$(unbundled_goals)"))
+  endif
+  TARGET_BUILD_APPS := $(strip $(subst -, ,$(patsubst APP-%,%,$(unbundled_goals))))
+  ifneq ($(filter $(DEFAULT_GOAL),$(MAKECMDGOALS)),)
+    MAKECMDGOALS := $(patsubst $(unbundled_goals),,$(MAKECMDGOALS))
+  else
+    MAKECMDGOALS := $(patsubst $(unbundled_goals),$(DEFAULT_GOAL),$(MAKECMDGOALS))
+  endif
+
+.PHONY: $(unbundled_goals)
+$(unbundled_goals): $(MAKECMDGOALS)
+endif # unbundled_goals
+
+# ---------------------------------------------------------------
 # Include the product definitions.
 # We need to do this to translate TARGET_PRODUCT into its
 # underlying TARGET_DEVICE before we start defining any rules.
@@ -157,12 +177,18 @@
 include $(BUILD_SYSTEM)/product.mk
 include $(BUILD_SYSTEM)/device.mk
 
-# Read in all of the product definitions specified by the AndroidProducts.mk
-# files in the tree.
-#
-#TODO: when we start allowing direct pointers to product files,
-#    guarantee that they're in this list.
-$(call import-products, $(get-all-product-makefiles))
+ifneq ($(strip $(TARGET_BUILD_APPS)),)
+  # An unbundled app build needs only the core product makefiles.
+  $(call import-products,$(call get-product-makefiles,\
+      $(SRC_TARGET_DIR)/product/AndroidProducts.mk))
+else
+  # Read in all of the product definitions specified by the AndroidProducts.mk
+  # files in the tree.
+  #
+  #TODO: when we start allowing direct pointers to product files,
+  #    guarantee that they're in this list.
+  $(call import-products, $(get-all-product-makefiles))
+endif # TARGET_BUILD_APPS
 $(check-all-products)
 #$(dump-products)
 #$(error done)
diff --git a/core/tasks/apicheck.mk b/core/tasks/apicheck.mk
index 044e4af..740668c 100644
--- a/core/tasks/apicheck.mk
+++ b/core/tasks/apicheck.mk
@@ -41,13 +41,18 @@
 # Run the checkapi rules by default.
 droidcore: checkapi
 
+last_released_sdk_version := $(lastword $(call numerically_sort,\
+    $(patsubst $(SRC_API_DIR)/%.xml,%, \
+    $(filter-out $(SRC_API_DIR)/current.xml, \
+    $(wildcard $(SRC_API_DIR)/*.xml)))))
+
 # INTERNAL_PLATFORM_API_FILE is the one build by droiddoc.
 
 # Check that the API we're building hasn't broken the last-released
 # SDK version.
 $(eval $(call check-api, \
 	checkapi-last, \
-	$(SRC_API_DIR)/$(lastword $(TARGET_AVAILABLE_SDK_VERSIONS)).xml, \
+	$(SRC_API_DIR)/$(last_released_sdk_version).xml, \
 	$(INTERNAL_PLATFORM_API_FILE), \
 	-hide 2 -hide 3 -hide 4 -hide 5 -hide 6 -hide 24 -hide 25 \
 	-error 7 -error 8 -error 9 -error 10 -error 11 -error 12 -error 13 -error 14 -error 15 \
diff --git a/envsetup.sh b/envsetup.sh
index 85465b1..21a66c1 100644
--- a/envsetup.sh
+++ b/envsetup.sh
@@ -56,6 +56,7 @@
     CALLED_FROM_SETUP=true BUILD_SYSTEM=build/core \
         TARGET_PRODUCT=$1 TARGET_BUILD_VARIANT= \
         TARGET_SIMULATOR= TARGET_BUILD_TYPE= \
+        TARGET_BUILD_APPS= \
         get_build_var TARGET_DEVICE > /dev/null
     # hide successful answers, but allow the errors to show
 }
@@ -150,9 +151,14 @@
 function settitle()
 {
     if [ "$STAY_OFF_MY_LAWN" = "" ]; then
-        local product=$(get_build_var TARGET_PRODUCT)
-        local variant=$(get_build_var TARGET_BUILD_VARIANT)
-        export PROMPT_COMMAND="echo -ne \"\033]0;[${product}-${variant}] ${USER}@${HOSTNAME}: ${PWD}\007\""
+        local product=$TARGET_PRODUCT
+        local variant=$TARGET_BUILD_VARIANT
+        local apps=$TARGET_BUILD_APPS
+        if [ -z "$apps" ]; then
+            export PROMPT_COMMAND="echo -ne \"\033]0;[${product}-${variant}] ${USER}@${HOSTNAME}: ${PWD}\007\""
+        else
+            export PROMPT_COMMAND="echo -ne \"\033]0;[$apps $variant] ${USER}@${HOSTNAME}: ${PWD}\007\""
+        fi
     fi
 }
 
@@ -376,11 +382,6 @@
     done
 }
 
-function tapas()
-{
-    choosecombo
-}
-
 function choosecombo()
 {
     choosesim $1
@@ -432,7 +433,6 @@
     echo
     echo "You're building on" $uname
     echo
-    echo ${LUNCH_MENU_CHOICES[@]}
     echo "Lunch menu... pick a combo:"
 
     local i=1
@@ -484,6 +484,8 @@
         return 1
     fi
 
+    export TARGET_BUILD_APPS=
+
     # special case the simulator
     if [ "$selection" = "simulator" ]
     then
@@ -530,6 +532,34 @@
     printconfig
 }
 
+# Configures the build to build unbundled apps.
+# Run tapas with one ore more app names (from LOCAL_PACKAGE_NAME)
+function tapas()
+{
+    local variant=$(echo -n $(echo $* | xargs -n 1 echo | grep -E '^(user|userdebug|eng)$'))
+    local apps=$(echo -n $(echo $* | xargs -n 1 echo | grep -E -v '^(user|userdebug|eng)$'))
+
+    if [ $(echo $variant | wc -w) -gt 1 ]; then
+        echo "tapas: Error: Multiple build variants supplied: $variant"
+        return
+    fi
+    if [ -z "$variant" ]; then
+        variant=eng
+    fi
+    if [ -z "$apps" ]; then
+        apps=all
+    fi
+
+    export TARGET_PRODUCT=generic
+    export TARGET_BUILD_VARIANT=$variant
+    export TARGET_SIMULATOR=false
+    export TARGET_BUILD_TYPE=release
+    export TARGET_BUILD_APPS=$apps
+
+    set_stuff_for_environment
+    printconfig
+}
+
 function gettop
 {
     local TOPFILE=build/core/envsetup.mk
@@ -1026,6 +1056,20 @@
     cd $T/$pathname
 }
 
+# Force JAVA_HOME to point to java 1.5 if it isn't already set
+if [ "$STAY_OFF_MY_LAWN" = "" ]; then
+    if [ ! "$JAVA_HOME" ]; then
+        case `uname -s` in
+            Darwin)
+                export JAVA_HOME=/System/Library/Frameworks/JavaVM.framework/Versions/1.5/Home
+                ;;
+            *)
+                export JAVA_HOME=/usr/lib/jvm/java-1.5.0-sun
+                ;;
+        esac
+    fi
+fi
+
 # determine whether arrays are zero-based (bash) or one-based (zsh)
 _xarray=(a b c)
 if [ -z "${_xarray[${#_xarray[@]}]}" ]
diff --git a/target/product/AndroidProducts.mk b/target/product/AndroidProducts.mk
index 2774968..3581da3 100644
--- a/target/product/AndroidProducts.mk
+++ b/target/product/AndroidProducts.mk
@@ -25,9 +25,16 @@
 # it includes.
 #
 
+# An unbundled app build needs only generic.mk.
+ifneq ($(TARGET_BUILD_APPS),)
+PRODUCT_MAKEFILES := \
+    $(LOCAL_DIR)/core.mk \
+    $(LOCAL_DIR)/generic.mk
+else
 PRODUCT_MAKEFILES := \
     $(LOCAL_DIR)/core.mk \
     $(LOCAL_DIR)/generic.mk \
     $(LOCAL_DIR)/full.mk \
     $(LOCAL_DIR)/sdk.mk \
     $(LOCAL_DIR)/sim.mk
+endif
diff --git a/target/product/sdk.mk b/target/product/sdk.mk
index c0e6c6d..be41486 100644
--- a/target/product/sdk.mk
+++ b/target/product/sdk.mk
@@ -48,7 +48,8 @@
 	ApiDemos \
 	GestureBuilder \
 	SoftKeyboard \
-	CubeLiveWallpapers
+	CubeLiveWallpapers \
+	QuickSearchBox
 
 PRODUCT_PACKAGE_OVERLAYS := development/sdk_overlay
 
diff --git a/tools/Android.mk b/tools/Android.mk
new file mode 100644
index 0000000..fa9d0b7
--- /dev/null
+++ b/tools/Android.mk
@@ -0,0 +1,24 @@
+#
+# Copyright (C) 2010 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.
+#
+
+LOCAL_PATH := $(my-dir)
+
+# If we're building only unbundled apps, this is the only tool we need.
+ifneq ($(TARGET_BUILD_APPS),)
+include $(LOCAL_PATH)/signapk/Android.mk
+else
+include $(call first-makefiles-under,$(LOCAL_PATH))
+endif
diff --git a/tools/droiddoc/templates/assets/images/home/froyo-android.png b/tools/droiddoc/templates/assets/images/home/froyo-android.png
index e5f2f35..c63f7f0 100644
--- a/tools/droiddoc/templates/assets/images/home/froyo-android.png
+++ b/tools/droiddoc/templates/assets/images/home/froyo-android.png
Binary files differ
diff --git a/tools/releasetools/ota_from_target_files b/tools/releasetools/ota_from_target_files
index cf5fb34..932d5b0 100755
--- a/tools/releasetools/ota_from_target_files
+++ b/tools/releasetools/ota_from_target_files
@@ -355,6 +355,7 @@
 
   metadata = {"post-build": GetBuildProp("ro.build.fingerprint", input_zip),
               "pre-device": GetBuildProp("ro.product.device", input_zip),
+              "post-timestamp": GetBuildProp("ro.build.date.utc", input_zip),
               }
 
   device_specific = common.DeviceSpecificParams(
@@ -602,6 +603,7 @@
     raise ValueError('unknown script mode "%s"' % (OPTIONS.script_mode,))
 
   metadata = {"pre-device": GetBuildProp("ro.product.device", source_zip),
+              "post-timestamp": GetBuildProp("ro.build.date.utc", target_zip),
               }
 
   device_specific = common.DeviceSpecificParams(
diff --git a/tools/signapk/Android.mk b/tools/signapk/Android.mk
index ccc76fd..b2de21c 100644
--- a/tools/signapk/Android.mk
+++ b/tools/signapk/Android.mk
@@ -23,5 +23,8 @@
 LOCAL_JAR_MANIFEST := SignApk.mf
 include $(BUILD_HOST_JAVA_LIBRARY)
 
-# The post-build signing tools need signapk.jar.
-$(call dist-for-goals,droid,$(LOCAL_INSTALLED_MODULE))
+ifeq ($(TARGET_BUILD_APPS),)
+# The post-build signing tools need signapk.jar, but we don't
+# need this if we're just doing unbundled apps.
+$(call dist-for-goals,droidcore,$(LOCAL_INSTALLED_MODULE))
+endif