diff --git a/CMakeLists.txt b/CMakeLists.txt
index 723f399..22a6a0b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -142,59 +142,32 @@
   endif (BUILD_TESTING AND BUILD_SHARED_LIBS)
 endif (MSVC)
 
-# Use ios-cmake to build a static library for iOS
-#
-# We need to add isysroot to force cmake to find the toolchains from the iOS SDK
-# instead of using the standard ones. And add flag mios-simulator-version so
-# clang knows we are building for ios simulator but not mac.
-#
-# You can build for OS (armv7, armv7s, arm64), SIMULATOR (i386) or SIMULATOR64
-# (x86_64) separately and use lipo to merge them into one static library.
-#
-# There are some features/algorithms are not available in iOS version and the
-# minimum supported iOS version is now 7.0.
-#
-# Use cmake ../ceres-solver -DCMAKE_TOOLCHAIN_FILE=../ceres-solver/cmake/iOS.cmake \
-# -DIOS_PLATFORM=PLATFORM -DEIGEN_INCLUDE_DIR=/path/to/eigen/header
-# to config the cmake. The PLATFORM can be one of OS, SIMULATOR and SIMULATOR64.
-# Check the documentation in iOS.cmake to find more options.
-#
-# After building, you will get a single library: libceres.a, which
-# you need to add to your Xcode project.
-#
-# If you use the lapack and blas, then you also need to add Accelerate.framework
-# to your Xcode project's linking dependency.
+# IOS is defined iff using the iOS.cmake CMake toolchain to build a static
+# library for iOS.
 if (IOS)
   message(STATUS "Building Ceres for iOS platform: ${IOS_PLATFORM}")
 
+  # Ceres requires at least iOS 7.0+.
+  if (IOS_SDK_VERSION VERSION_LESS 7.0)
+    message(FATAL_ERROR "Unsupported iOS SDK version: ${IOS_SDK_VERSION}, Ceres "
+      "required at least iOS version 7.0")
+  endif()
+
   update_cache_variable(MINIGLOG ON)
-  message(STATUS "Building for iOS, forcing use of miniglog instead of glog.")
+  message(STATUS "Building for iOS: Forcing use of miniglog instead of glog.")
 
   update_cache_variable(SUITESPARSE OFF)
   update_cache_variable(CXSPARSE OFF)
   update_cache_variable(GFLAGS OFF)
   update_cache_variable(OPENMP OFF)
-
   # Apple claims that the BLAS call dsyrk_ is a private API, and will not allow
   # you to submit to the Apple Store if the symbol is present.
   update_cache_variable(LAPACK OFF)
-
   message(STATUS "Building for iOS: SuiteSparse, CXSparse, LAPACK, gflags, "
     "and OpenMP are not available.")
 
   update_cache_variable(BUILD_EXAMPLES OFF)
-  message(STATUS "Building for iOS, will not build examples.")
-
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fobjc-abi-version=2 -fobjc-arc -isysroot ${CMAKE_OSX_SYSROOT}")
-  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fobjc-abi-version=2 -fobjc-arc -isysroot ${CMAKE_OSX_SYSROOT}")
-
-   if (${IOS_PLATFORM} STREQUAL "SIMULATOR" OR
-       ${IOS_PLATFORM} STREQUAL "SIMULATOR64")
-     # By default, the minimum version is < 7.0, which causes problems with
-     # detection of shared_ptr & unordered_map as pre-7.0 used libstdc++
-     # but 7.0+ uses libc++ (also LLVM-GCC was removed from Xcode 5).
-     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mios-simulator-version-min=7.0")
-   endif()
+  message(STATUS "Building for iOS: Will not build examples.")
 endif (IOS)
 
 unset(CERES_COMPILE_OPTIONS)
@@ -445,6 +418,7 @@
   set(CMAKE_REQUIRED_FLAGS -std=c++11)
 endif (CXX11 AND COMPILER_HAS_CXX11_FLAG)
 
+# Set the Ceres compile definitions for the unordered_map configuration.
 include(FindUnorderedMap)
 find_unordered_map()
 if (UNORDERED_MAP_FOUND)
@@ -463,6 +437,7 @@
   list(APPEND CERES_COMPILE_OPTIONS CERES_NO_UNORDERED_MAP)
 endif()
 
+# Set the Ceres compile definitions for the shared_ptr configuration.
 include(FindSharedPtr)
 find_shared_ptr()
 if (SHARED_PTR_FOUND)
diff --git a/cmake/iOS.cmake b/cmake/iOS.cmake
index 8b8b40d..a22fcb5 100644
--- a/cmake/iOS.cmake
+++ b/cmake/iOS.cmake
@@ -37,208 +37,258 @@
 # ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 # POSSIBILITY OF SUCH DAMAGE.
 #
-# This file is based off of the Platform/Darwin.cmake and Platform/UnixPaths.cmake
-# files which are included with CMake 2.8.4
-# It has been altered for iOS development
+# This file is based off of the Platform/Darwin.cmake and
+# Platform/UnixPaths.cmake files which are included with CMake 2.8.4
+# It has been altered for iOS development.
+#
+# Updated by Alex Stewart (alexs.mac@gmail.com).
 
-# Options:
+# The following variables control the behaviour of this toolchain:
 #
-# IOS_PLATFORM = OS (default) or SIMULATOR or SIMULATOR64
-#   This decides if SDKS will be selected from the iPhoneOS.platform or iPhoneSimulator.platform folders
-#   OS - the default, used to build for iPhone and iPad physical devices, which have an arm arch.
-#   SIMULATOR - used to build for the Simulator platforms, which have an x86 arch.
+# IOS_PLATFORM: OS (default) or SIMULATOR or SIMULATOR64
+#    OS = Build for iPhoneOS.
+#    SIMULATOR = Build for x86 i386 iPhone Simulator.
+#    SIMULATOR64 = Build for x86 x86_64 iPhone Simulator.
+# CMAKE_OSX_SYSROOT: Path to the iOS SDK to use.  By default this is
+#    automatically determined from IOS_PLATFORM and xcodebuild, but
+#    can also be manually specified (although this should not be required).
+# CMAKE_IOS_DEVELOPER_ROOT: Path to the Developer directory for the iOS platform
+#    being compiled for.  By default this is automatically determined from
+#    CMAKE_OSX_SYSROOT, but can also be manually specified (although this should
+#    not be required).
 #
-# CMAKE_IOS_DEVELOPER_ROOT = automatic(default) or /path/to/platform/Developer folder
-#   By default this location is automatcially chosen based on the IOS_PLATFORM value above.
-#   If set manually, it will override the default location and force the user of a particular Developer Platform
+# This toolchain defines the following variables for use externally:
 #
-# CMAKE_IOS_SDK_ROOT = automatic(default) or /path/to/platform/Developer/SDKs/SDK folder
-#   By default this location is automatcially chosen based on the CMAKE_IOS_DEVELOPER_ROOT value.
-#   In this case it will always be the most up-to-date SDK found in the CMAKE_IOS_DEVELOPER_ROOT path.
-#   If set manually, this will force the use of a specific SDK version
-
-# Macros:
+# IOS_SDK_VERSION: Version of iOS SDK being used.
+# CMAKE_OSX_ARCHITECTURES: Architectures being compiled for (generated from
+#    IOS_PLATFORM).
+#
+# This toolchain defines the following macros for use externally:
 #
 # set_xcode_property (TARGET XCODE_PROPERTY XCODE_VALUE)
-#  A convenience macro for setting xcode specific properties on targets
-#  example: set_xcode_property (myioslib IPHONEOS_DEPLOYMENT_TARGET "3.1")
+#   A convenience macro for setting xcode specific properties on targets
+#   example: set_xcode_property (myioslib IPHONEOS_DEPLOYMENT_TARGET "3.1").
 #
 # find_host_package (PROGRAM ARGS)
-#  A macro used to find executable programs on the host system, not within the iOS environment.
-#  Thanks to the android-cmake project for providing the command
+#   A macro used to find executable programs on the host system, not within the
+#   iOS environment.  Thanks to the android-cmake project for providing the
+#   command.
 
-# Standard settings
-set (CMAKE_SYSTEM_NAME Darwin)
-set (CMAKE_SYSTEM_VERSION 1)
-set (UNIX True)
-set (APPLE True)
-set (IOS True)
+# Default to building for iPhoneOS if not specified otherwise, and we cannot
+# determine the platform from the CMAKE_OSX_ARCHITECTURES variable.  The use
+# of CMAKE_OSX_ARCHITECTURES is such that try_compile() projects can correctly
+# determine the value of IOS_PLATFORM from the root project, as
+# CMAKE_OSX_ARCHITECTURES is propagated to them by CMake.
+if (NOT DEFINED IOS_PLATFORM)
+  if (CMAKE_OSX_ARCHITECTURES)
+    if (CMAKE_OSX_ARCHITECTURES MATCHES ".*arm.*")
+      set(IOS_PLATFORM "OS")
+    elseif (CMAKE_OSX_ARCHITECTURES MATCHES "i386")
+      set(IOS_PLATFORM "SIMULATOR")
+    elseif (CMAKE_OSX_ARCHITECTURES MATCHES "x86_64")
+      set(IOS_PLATFORM "SIMULATOR64")
+    endif()
+  endif()
+  if (NOT IOS_PLATFORM)
+    set(IOS_PLATFORM "OS")
+  endif()
+endif()
+set(IOS_PLATFORM ${IOS_PLATFORM} CACHE STRING
+  "Type of iOS platform for which to build.")
 
-# Required as of cmake 2.8.10
-set (CMAKE_OSX_DEPLOYMENT_TARGET "" CACHE STRING "Force unset of the deployment target for iOS" FORCE)
+# Determine the platform name and architectures for use in xcodebuild commands
+# from the specified IOS_PLATFORM name.
+if (IOS_PLATFORM STREQUAL "OS")
+  set(XCODE_IOS_PLATFORM iphoneos)
+  set(IOS_ARCH armv7 armv7s arm64)
+elseif (IOS_PLATFORM STREQUAL "SIMULATOR")
+  set(XCODE_IOS_PLATFORM iphonesimulator)
+  set(IOS_ARCH i386)
+elseif(IOS_PLATFORM STREQUAL "SIMULATOR64")
+  set(XCODE_IOS_PLATFORM iphonesimulator)
+  set(IOS_ARCH x86_64)
+else()
+  message(FATAL_ERROR "Invalid IOS_PLATFORM: ${IOS_PLATFORM}")
+endif()
 
-# Determine the cmake host system version so we know where to find the iOS SDKs
-find_program (CMAKE_UNAME uname /bin /usr/bin /usr/local/bin)
-if (CMAKE_UNAME)
-	exec_program(uname ARGS -r OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_VERSION)
-	string (REGEX REPLACE "^([0-9]+)\\.([0-9]+).*$" "\\1" DARWIN_MAJOR_VERSION "${CMAKE_HOST_SYSTEM_VERSION}")
-endif (CMAKE_UNAME)
+message(STATUS "Configuring iOS build for platform: ${IOS_PLATFORM}, "
+  "architecture(s): ${IOS_ARCH}")
 
-set(CMAKE_C_COMPIER clang)
-set(CMAKE_CXX_COMPIER clang++)
-set(CMAKE_AR ar CACHE FILEPATH "" FORCE)
+# If user did not specify the SDK root to use, then query xcodebuild for it.
+if (NOT CMAKE_OSX_SYSROOT)
+  execute_process(COMMAND xcodebuild -version -sdk ${XCODE_IOS_PLATFORM} Path
+    OUTPUT_VARIABLE CMAKE_OSX_SYSROOT
+    ERROR_QUIET
+    OUTPUT_STRIP_TRAILING_WHITESPACE)
+  message(STATUS "Using SDK: ${CMAKE_OSX_SYSROOT} for platform: ${IOS_PLATFORM}")
+endif()
+if (NOT EXISTS ${CMAKE_OSX_SYSROOT})
+  message(FATAL_ERROR "Invalid CMAKE_OSX_SYSROOT: ${CMAKE_OSX_SYSROOT} "
+    "does not exist.")
+endif()
+# Get the SDK version information.
+execute_process(COMMAND xcodebuild -sdk ${CMAKE_OSX_SYSROOT} -version SDKVersion
+  OUTPUT_VARIABLE IOS_SDK_VERSION
+  ERROR_QUIET
+  OUTPUT_STRIP_TRAILING_WHITESPACE)
 
-# Skip the platform compiler checks for cross compiling
-set (CMAKE_CXX_COMPILER_WORKS TRUE)
-set (CMAKE_C_COMPILER_WORKS TRUE)
+# Find the Developer root for the specific iOS platform being compiled for
+# from CMAKE_OSX_SYSROOT.  Should be ../../ from SDK specified in
+# CMAKE_OSX_SYSROOT.  There does not appear to be a direct way to obtain
+# this information from xcrun or xcodebuild.
+if (NOT CMAKE_IOS_DEVELOPER_ROOT)
+  get_filename_component(IOS_PLATFORM_SDK_DIR ${CMAKE_OSX_SYSROOT} PATH)
+  get_filename_component(CMAKE_IOS_DEVELOPER_ROOT ${IOS_PLATFORM_SDK_DIR} PATH)
+endif()
+if (NOT EXISTS ${CMAKE_IOS_DEVELOPER_ROOT})
+  message(FATAL_ERROR "Invalid CMAKE_IOS_DEVELOPER_ROOT: "
+    "${CMAKE_IOS_DEVELOPER_ROOT} does not exist.")
+endif()
 
-# All iOS/Darwin specific settings - some may be redundant
-set (CMAKE_SHARED_LIBRARY_PREFIX "lib")
-set (CMAKE_SHARED_LIBRARY_SUFFIX ".dylib")
-set (CMAKE_SHARED_MODULE_PREFIX "lib")
-set (CMAKE_SHARED_MODULE_SUFFIX ".so")
-set (CMAKE_MODULE_EXISTS 1)
-set (CMAKE_DL_LIBS "")
+# Find the C & C++ compilers for the specified SDK.
+if (NOT CMAKE_C_COMPILER)
+  execute_process(COMMAND xcrun -sdk ${CMAKE_OSX_SYSROOT} -find clang
+    OUTPUT_VARIABLE CMAKE_C_COMPILER
+    ERROR_QUIET
+    OUTPUT_STRIP_TRAILING_WHITESPACE)
+  message(STATUS "Using C compiler: ${CMAKE_C_COMPILER}")
+endif()
+if (NOT CMAKE_CXX_COMPILER)
+  execute_process(COMMAND xcrun -sdk ${CMAKE_OSX_SYSROOT} -find clang++
+    OUTPUT_VARIABLE CMAKE_CXX_COMPILER
+    ERROR_QUIET
+    OUTPUT_STRIP_TRAILING_WHITESPACE)
+  message(STATUS "Using CXX compiler: ${CMAKE_CXX_COMPILER}")
+endif()
 
-set (CMAKE_C_OSX_COMPATIBILITY_VERSION_FLAG "-compatibility_version ")
-set (CMAKE_C_OSX_CURRENT_VERSION_FLAG "-current_version ")
-set (CMAKE_CXX_OSX_COMPATIBILITY_VERSION_FLAG "${CMAKE_C_OSX_COMPATIBILITY_VERSION_FLAG}")
-set (CMAKE_CXX_OSX_CURRENT_VERSION_FLAG "${CMAKE_C_OSX_CURRENT_VERSION_FLAG}")
+# Find (Apple's) libtool.
+execute_process(COMMAND xcrun -sdk ${CMAKE_OSX_SYSROOT} -find libtool
+  OUTPUT_VARIABLE IOS_LIBTOOL
+  ERROR_QUIET
+  OUTPUT_STRIP_TRAILING_WHITESPACE)
+message(STATUS "Using libtool: ${IOS_LIBTOOL}")
+# Configure libtool to be used instead of ar + ranlib to build static libraries.
+# This is required on Xcode 7+, but should also work on previous versions of
+# Xcode.
+set(CMAKE_C_CREATE_STATIC_LIBRARY
+  "${IOS_LIBTOOL} -static -o <TARGET> <LINK_FLAGS> <OBJECTS> ")
+set(CMAKE_CXX_CREATE_STATIC_LIBRARY
+  "${IOS_LIBTOOL} -static -o <TARGET> <LINK_FLAGS> <OBJECTS> ")
 
-# Hidden visibilty is required for cxx on iOS
-set (CMAKE_C_FLAGS_INIT "")
-set (CMAKE_CXX_FLAGS_INIT "-fvisibility=hidden -fvisibility-inlines-hidden")
-set (CMAKE_CXX_FLAGS_RELEASE_INIT "-DNDEBUG -O3 -fomit-frame-pointer -ffast-math")
+# Get the version of Darwin (OS X) of the host.
+execute_process(COMMAND uname -r
+  OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_VERSION
+  ERROR_QUIET
+  OUTPUT_STRIP_TRAILING_WHITESPACE)
 
-set (CMAKE_C_LINK_FLAGS "-Wl,-search_paths_first ${CMAKE_C_LINK_FLAGS}")
-set (CMAKE_CXX_LINK_FLAGS "-Wl,-search_paths_first ${CMAKE_CXX_LINK_FLAGS}")
+# Standard settings.
+set(CMAKE_SYSTEM_NAME Darwin)
+set(CMAKE_SYSTEM_VERSION ${IOS_SDK_VERSION})
+set(UNIX TRUE)
+set(APPLE TRUE)
+set(IOS TRUE)
+# Force unset of OS X-specific deployment target (otherwise autopopulated),
+# required as of cmake 2.8.10.
+set(CMAKE_OSX_DEPLOYMENT_TARGET "" CACHE STRING
+  "Must be empty for iOS builds." FORCE)
+# Set the architectures for which to build.
+set(CMAKE_OSX_ARCHITECTURES ${IOS_ARCH} CACHE STRING "Build architecture for iOS")
 
-set (CMAKE_PLATFORM_HAS_INSTALLNAME 1)
-set (CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS "-dynamiclib -headerpad_max_install_names")
-set (CMAKE_SHARED_MODULE_CREATE_C_FLAGS "-bundle -headerpad_max_install_names")
-set (CMAKE_SHARED_MODULE_LOADER_C_FLAG "-Wl,-bundle_loader,")
-set (CMAKE_SHARED_MODULE_LOADER_CXX_FLAG "-Wl,-bundle_loader,")
-set (CMAKE_FIND_LIBRARY_SUFFIXES ".dylib" ".so" ".a")
+# Skip the platform compiler checks for cross compiling.
+set(CMAKE_CXX_COMPILER_FORCED TRUE)
+set(CMAKE_CXX_COMPILER_WORKS TRUE)
+set(CMAKE_C_COMPILER_FORCED TRUE)
+set(CMAKE_C_COMPILER_WORKS TRUE)
 
-# hack: if a new cmake (which uses CMAKE_INSTALL_NAME_TOOL) runs on an old build tree
-# (where install_name_tool was hardcoded) and where CMAKE_INSTALL_NAME_TOOL isn't in the cache
-# and still cmake didn't fail in CMakeFindBinUtils.cmake (because it isn't rerun)
-# hardcode CMAKE_INSTALL_NAME_TOOL here to install_name_tool, so it behaves as it did before, Alex
+# All iOS/Darwin specific settings - some may be redundant.
+set(CMAKE_SHARED_LIBRARY_PREFIX "lib")
+set(CMAKE_SHARED_LIBRARY_SUFFIX ".dylib")
+set(CMAKE_SHARED_MODULE_PREFIX "lib")
+set(CMAKE_SHARED_MODULE_SUFFIX ".so")
+set(CMAKE_MODULE_EXISTS 1)
+set(CMAKE_DL_LIBS "")
+
+set(CMAKE_C_OSX_COMPATIBILITY_VERSION_FLAG "-compatibility_version ")
+set(CMAKE_C_OSX_CURRENT_VERSION_FLAG "-current_version ")
+set(CMAKE_CXX_OSX_COMPATIBILITY_VERSION_FLAG "${CMAKE_C_OSX_COMPATIBILITY_VERSION_FLAG}")
+set(CMAKE_CXX_OSX_CURRENT_VERSION_FLAG "${CMAKE_C_OSX_CURRENT_VERSION_FLAG}")
+
+# Specify minimum version as latest SDK version.
+set(CMAKE_C_FLAGS
+  "-m${XCODE_IOS_PLATFORM}-version-min=${IOS_SDK_VERSION} -fobjc-abi-version=2 -fobjc-arc ${CMAKE_C_FLAGS}")
+# Hidden visibilty is required for C++ on iOS.
+set(CMAKE_CXX_FLAGS
+  "-m${XCODE_IOS_PLATFORM}-version-min=${IOS_SDK_VERSION} -fvisibility=hidden -fvisibility-inlines-hidden -fobjc-abi-version=2 -fobjc-arc ${CMAKE_CXX_FLAGS}")
+set(CMAKE_CXX_FLAGS_RELEASE "-DNDEBUG -O3 -fomit-frame-pointer -ffast-math ${CMAKE_CXX_FLAGS_RELEASE}")
+
+set(CMAKE_C_LINK_FLAGS "-m${XCODE_IOS_PLATFORM}-version-min=${IOS_SDK_VERSION} -Wl,-search_paths_first ${CMAKE_C_LINK_FLAGS}")
+set(CMAKE_CXX_LINK_FLAGS "-m${XCODE_IOS_PLATFORM}-version-min=${IOS_SDK_VERSION}  -Wl,-search_paths_first ${CMAKE_CXX_LINK_FLAGS}")
+
+# In order to ensure that the updated compiler flags are used in try_compile()
+# tests, we have to forcibly set them in the CMake cache, not merely set them
+# in the local scope.
+list(APPEND VARS_TO_FORCE_IN_CACHE
+  CMAKE_C_FLAGS
+  CMAKE_CXX_FLAGS
+  CMAKE_CXX_RELEASE
+  CMAKE_C_LINK_FLAGS
+  CMAKE_CXX_LINK_FLAGS)
+foreach(VAR_TO_FORCE ${VARS_TO_FORCE_IN_CACHE})
+  set(${VAR_TO_FORCE} "${${VAR_TO_FORCE}}" CACHE STRING "" FORCE)
+endforeach()
+
+set(CMAKE_PLATFORM_HAS_INSTALLNAME 1)
+set(CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS "-dynamiclib -headerpad_max_install_names")
+set(CMAKE_SHARED_MODULE_CREATE_C_FLAGS "-bundle -headerpad_max_install_names")
+set(CMAKE_SHARED_MODULE_LOADER_C_FLAG "-Wl,-bundle_loader,")
+set(CMAKE_SHARED_MODULE_LOADER_CXX_FLAG "-Wl,-bundle_loader,")
+set(CMAKE_FIND_LIBRARY_SUFFIXES ".dylib" ".so" ".a")
+
+# Hack: if a new cmake (which uses CMAKE_INSTALL_NAME_TOOL) runs on an old
+# build tree (where install_name_tool was hardcoded) and where
+# CMAKE_INSTALL_NAME_TOOL isn't in the cache and still cmake didn't fail in
+# CMakeFindBinUtils.cmake (because it isn't rerun) hardcode
+# CMAKE_INSTALL_NAME_TOOL here to install_name_tool, so it behaves as it did
+# before, Alex.
 if (NOT DEFINED CMAKE_INSTALL_NAME_TOOL)
-	find_program(CMAKE_INSTALL_NAME_TOOL install_name_tool)
+  find_program(CMAKE_INSTALL_NAME_TOOL install_name_tool)
 endif (NOT DEFINED CMAKE_INSTALL_NAME_TOOL)
 
-# Setup iOS platform unless specified manually with IOS_PLATFORM
-if (NOT DEFINED IOS_PLATFORM)
-	set (IOS_PLATFORM "OS")
-endif (NOT DEFINED IOS_PLATFORM)
-set (IOS_PLATFORM ${IOS_PLATFORM} CACHE STRING "Type of iOS Platform")
+# Set the find root to the iOS developer roots and to user defined paths.
+set(CMAKE_FIND_ROOT_PATH ${CMAKE_IOS_DEVELOPER_ROOT} ${CMAKE_OSX_SYSROOT}
+  ${CMAKE_PREFIX_PATH} CACHE string  "iOS find search path root" FORCE)
 
-# Setup building for arm64 or not
-if (NOT DEFINED BUILD_ARM64)
-    set (BUILD_ARM64 true)
-endif (NOT DEFINED BUILD_ARM64)
-set (BUILD_ARM64 ${BUILD_ARM64} CACHE STRING "Build arm64 arch or not")
+# Default to searching for frameworks first.
+set(CMAKE_FIND_FRAMEWORK FIRST)
 
-# Check the platform selection and setup for developer root
-if (${IOS_PLATFORM} STREQUAL "OS")
-	set (IOS_PLATFORM_LOCATION "iPhoneOS.platform")
+# Set up the default search directories for frameworks.
+set(CMAKE_SYSTEM_FRAMEWORK_PATH
+  ${CMAKE_OSX_SYSROOT}/System/Library/Frameworks
+  ${CMAKE_OSX_SYSROOT}/System/Library/PrivateFrameworks
+  ${CMAKE_OSX_SYSROOT}/Developer/Library/Frameworks)
 
-	# This causes the installers to properly locate the output libraries
-	set (CMAKE_XCODE_EFFECTIVE_PLATFORMS "-iphoneos")
-elseif (${IOS_PLATFORM} STREQUAL "SIMULATOR")
-    set (SIMULATOR true)
-	set (IOS_PLATFORM_LOCATION "iPhoneSimulator.platform")
+# Only search the specified iOS SDK, not the remainder of the host filesystem.
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
 
-	# This causes the installers to properly locate the output libraries
-	set (CMAKE_XCODE_EFFECTIVE_PLATFORMS "-iphonesimulator")
-elseif (${IOS_PLATFORM} STREQUAL "SIMULATOR64")
-    set (SIMULATOR true)
-	set (IOS_PLATFORM_LOCATION "iPhoneSimulator.platform")
+# This little macro lets you set any XCode specific property.
+macro(set_xcode_property TARGET XCODE_PROPERTY XCODE_VALUE)
+  set_property(TARGET ${TARGET} PROPERTY
+    XCODE_ATTRIBUTE_${XCODE_PROPERTY} ${XCODE_VALUE})
+endmacro(set_xcode_property)
 
-	# This causes the installers to properly locate the output libraries
-	set (CMAKE_XCODE_EFFECTIVE_PLATFORMS "-iphonesimulator")
-else (${IOS_PLATFORM} STREQUAL "OS")
-	message (FATAL_ERROR "Unsupported IOS_PLATFORM value selected. Please choose OS or SIMULATOR")
-endif (${IOS_PLATFORM} STREQUAL "OS")
+# This macro lets you find executable programs on the host system.
+macro(find_host_package)
+  set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+  set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY NEVER)
+  set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE NEVER)
+  set(IOS FALSE)
 
-# Setup iOS developer location unless specified manually with CMAKE_IOS_DEVELOPER_ROOT
-# Note Xcode 4.3 changed the installation location, choose the most recent one available
-set (XCODE_POST_43_ROOT "/Applications/Xcode.app/Contents/Developer/Platforms/${IOS_PLATFORM_LOCATION}/Developer")
-set (XCODE_PRE_43_ROOT "/Developer/Platforms/${IOS_PLATFORM_LOCATION}/Developer")
-if (NOT DEFINED CMAKE_IOS_DEVELOPER_ROOT)
-	if (EXISTS ${XCODE_POST_43_ROOT})
-		set (CMAKE_IOS_DEVELOPER_ROOT ${XCODE_POST_43_ROOT})
-	elseif(EXISTS ${XCODE_PRE_43_ROOT})
-		set (CMAKE_IOS_DEVELOPER_ROOT ${XCODE_PRE_43_ROOT})
-	endif (EXISTS ${XCODE_POST_43_ROOT})
-endif (NOT DEFINED CMAKE_IOS_DEVELOPER_ROOT)
-set (CMAKE_IOS_DEVELOPER_ROOT ${CMAKE_IOS_DEVELOPER_ROOT} CACHE PATH "Location of iOS Platform")
+  find_package(${ARGN})
 
-# Find and use the most recent iOS sdk unless specified manually with CMAKE_IOS_SDK_ROOT
-if (NOT DEFINED CMAKE_IOS_SDK_ROOT)
-	file (GLOB _CMAKE_IOS_SDKS "${CMAKE_IOS_DEVELOPER_ROOT}/SDKs/*")
-	if (_CMAKE_IOS_SDKS)
-		list (SORT _CMAKE_IOS_SDKS)
-		list (REVERSE _CMAKE_IOS_SDKS)
-		list (GET _CMAKE_IOS_SDKS 0 CMAKE_IOS_SDK_ROOT)
-	else (_CMAKE_IOS_SDKS)
-		message (FATAL_ERROR "No iOS SDK's found in default search path ${CMAKE_IOS_DEVELOPER_ROOT}. Manually set CMAKE_IOS_SDK_ROOT or install the iOS SDK.")
-	endif (_CMAKE_IOS_SDKS)
-	message (STATUS "Toolchain using default iOS SDK: ${CMAKE_IOS_SDK_ROOT}")
-endif (NOT DEFINED CMAKE_IOS_SDK_ROOT)
-set (CMAKE_IOS_SDK_ROOT ${CMAKE_IOS_SDK_ROOT} CACHE PATH "Location of the selected iOS SDK")
-
-# Set the sysroot default to the most recent SDK
-set (CMAKE_OSX_SYSROOT ${CMAKE_IOS_SDK_ROOT} CACHE PATH "Sysroot used for iOS support")
-
-# set the architecture for iOS
-if (${IOS_PLATFORM} STREQUAL "OS")
-    set (IOS_ARCH armv7 armv7s arm64)
-elseif (${IOS_PLATFORM} STREQUAL "SIMULATOR")
-    set (IOS_ARCH i386)
-elseif (${IOS_PLATFORM} STREQUAL "SIMULATOR64")
-    set (IOS_ARCH x86_64)
-endif (${IOS_PLATFORM} STREQUAL "OS")
-
-set (CMAKE_OSX_ARCHITECTURES ${IOS_ARCH} CACHE string  "Build architecture for iOS")
-
-# Set the find root to the iOS developer roots and to user defined paths
-set (CMAKE_FIND_ROOT_PATH ${CMAKE_IOS_DEVELOPER_ROOT} ${CMAKE_IOS_SDK_ROOT} ${CMAKE_PREFIX_PATH} CACHE string  "iOS find search path root")
-
-# default to searching for frameworks first
-set (CMAKE_FIND_FRAMEWORK FIRST)
-
-# set up the default search directories for frameworks
-set (CMAKE_SYSTEM_FRAMEWORK_PATH
-	${CMAKE_IOS_SDK_ROOT}/System/Library/Frameworks
-	${CMAKE_IOS_SDK_ROOT}/System/Library/PrivateFrameworks
-	${CMAKE_IOS_SDK_ROOT}/Developer/Library/Frameworks
-)
-
-# only search the iOS sdks, not the remainder of the host filesystem
-set (CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY)
-set (CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
-set (CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
-
-
-# This little macro lets you set any XCode specific property
-macro (set_xcode_property TARGET XCODE_PROPERTY XCODE_VALUE)
-	set_property (TARGET ${TARGET} PROPERTY XCODE_ATTRIBUTE_${XCODE_PROPERTY} ${XCODE_VALUE})
-endmacro (set_xcode_property)
-
-
-# This macro lets you find executable programs on the host system
-macro (find_host_package)
-	set (CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
-	set (CMAKE_FIND_ROOT_PATH_MODE_LIBRARY NEVER)
-	set (CMAKE_FIND_ROOT_PATH_MODE_INCLUDE NEVER)
-	set (IOS FALSE)
-
-	find_package(${ARGN})
-
-	set (IOS TRUE)
-	set (CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY)
-	set (CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
-	set (CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
-endmacro (find_host_package)
+  set(IOS TRUE)
+  set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY)
+  set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+  set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+endmacro(find_host_package)
diff --git a/docs/source/building.rst b/docs/source/building.rst
index e8bd80c..f7d30d5 100644
--- a/docs/source/building.rst
+++ b/docs/source/building.rst
@@ -447,14 +447,15 @@
 
 .. code-block:: bash
 
-   cmake ../ceres-solver \
+   cmake \
    -DCMAKE_TOOLCHAIN_FILE=../ceres-solver/cmake/iOS.cmake \
    -DEIGEN_INCLUDE_DIR=/path/to/eigen/header \
-   -DIOS_PLATFORM=<PLATFORM>
+   -DIOS_PLATFORM=<PLATFORM> \
+   <PATH_TO_CERES_SOURCE>
 
-``PLATFORM`` can be one of ``OS``, ``SIMULATOR`` and ``SIMULATOR64``. You can
+``PLATFORM`` can be: ``OS``, ``SIMULATOR`` or ``SIMULATOR64``. You can
 build for ``OS`` (``armv7``, ``armv7s``, ``arm64``), ``SIMULATOR`` (``i386``) or
-``SIMULATOR64`` (``x86_64``) separately and use ``LIPO`` to merge them into
+``SIMULATOR64`` (``x86_64``) separately and use ``lipo`` to merge them into
 one static library.  See ``cmake/iOS.cmake`` for more options.
 
 After building, you will get a ``libceres.a`` library, which you will need to