diff --git a/common/platform_default.cpp b/common/platform_default.cpp
new file mode 100644
index 000000000..1acbfa850
--- /dev/null
+++ b/common/platform_default.cpp
@@ -0,0 +1,25 @@
+#include <mbgl/platform/platform.hpp>
+
+#include <locale>
+
+namespace mbgl {
+namespace platform {
+
+std::string uppercase(const std::string& string) {
+    // TODO: Use a proper Unicode Special Casing-aware algorithm.
+    const auto &convert = std::use_facet<std::ctype<char>>(std::locale());
+    std::string converted = string;
+    convert.toupper(&converted[0], &converted[0] + converted.size());
+    return converted;
+}
+
+std::string lowercase(const std::string& string) {
+    // TODO: Use a proper Unicode Special Casing-aware algorithm.
+    const auto &convert = std::use_facet<std::ctype<char>>(std::locale());
+    std::string converted = string;
+    convert.tolower(&converted[0], &converted[0] + converted.size());
+    return converted;
+}
+
+}
+}
diff --git a/common/platform_nsstring.mm b/common/platform_nsstring.mm
new file mode 100644
index 000000000..9119f2a8f
--- /dev/null
+++ b/common/platform_nsstring.mm
@@ -0,0 +1,21 @@
+#import <Foundation/Foundation.h>
+
+#include <mbgl/platform/platform.hpp>
+
+namespace mbgl {
+namespace platform {
+
+std::string uppercase(const std::string &string) {
+    NSString *nsstring = [[NSString alloc] initWithBytesNoCopy:const_cast<char *>(string.data()) length:string.size() encoding:NSUTF8StringEncoding freeWhenDone:NO];
+    nsstring = [nsstring uppercaseString];
+    return { [nsstring cStringUsingEncoding:NSUTF8StringEncoding], [nsstring lengthOfBytesUsingEncoding:NSUTF8StringEncoding] };
+}
+
+std::string lowercase(const std::string &string) {
+    NSString *nsstring = [[NSString alloc] initWithBytesNoCopy:const_cast<char *>(string.data()) length:string.size() encoding:NSUTF8StringEncoding freeWhenDone:NO];
+    nsstring = [nsstring lowercaseString];
+    return { [nsstring cStringUsingEncoding:NSUTF8StringEncoding], [nsstring lengthOfBytesUsingEncoding:NSUTF8StringEncoding] };
+}
+
+}
+}
\ No newline at end of file
diff --git a/include/mbgl/platform/platform.hpp b/include/mbgl/platform/platform.hpp
index 43c6ce4f5..22405a4cf 100644
--- a/include/mbgl/platform/platform.hpp
+++ b/include/mbgl/platform/platform.hpp
@@ -28,6 +28,12 @@ std::shared_ptr<Request> request_http(const std::string &url,
                                       std::function<void(Response *)> callback,
                                       std::shared_ptr<uv::loop> loop = nullptr);
 
+// Uppercase a string, potentially using platform-specific routines.
+std::string uppercase(const std::string &string);
+
+// Lowercase a string, potentially using platform-specific routines.
+std::string lowercase(const std::string &string);
+
 // Cancels an HTTP request.
 void cancel_request_http(const std::shared_ptr<Request> &req);
 
diff --git a/ios/mapbox-gl-cocoa b/ios/mapbox-gl-cocoa
index e1c709a8d..cf1f1da00 160000
--- a/ios/mapbox-gl-cocoa
+++ b/ios/mapbox-gl-cocoa
@@ -1 +1 @@
-Subproject commit e1c709a8de0b69aa6bfbcd9ea4faf981b6e799b2
+Subproject commit cf1f1da000a8a5f2867d70b3828bd5b692445d89
diff --git a/linux/mapboxgl-app.gyp b/linux/mapboxgl-app.gyp
index 7b703ed75..e19768caf 100644
--- a/linux/mapboxgl-app.gyp
+++ b/linux/mapboxgl-app.gyp
@@ -12,6 +12,7 @@
         './main.cpp',
         '../common/settings_json.cpp',
         '../common/settings_json.hpp',
+        '../common/platform_default.cpp',
         '../common/glfw_view.hpp',
         '../common/glfw_view.cpp',
         '../common/curl_request.cpp',
diff --git a/macosx/mapboxgl-app.gyp b/macosx/mapboxgl-app.gyp
index 480dc2a11..da5c68ea3 100644
--- a/macosx/mapboxgl-app.gyp
+++ b/macosx/mapboxgl-app.gyp
@@ -12,6 +12,7 @@
         './main.mm',
         '../common/settings_nsuserdefaults.hpp',
         '../common/settings_nsuserdefaults.mm',
+        '../common/platform_nsstring.mm',
         '../common/glfw_view.hpp',
         '../common/glfw_view.cpp',
         '../common/foundation_request.h',
diff --git a/scripts/travis_script.sh b/scripts/travis_script.sh
index a13d7531e..f8325e41c 100755
--- a/scripts/travis_script.sh
+++ b/scripts/travis_script.sh
@@ -17,11 +17,12 @@ elif [[ ${TRAVIS_OS_NAME} == "osx" ]]; then
     # build OS X
     #
     make xproj-cli
-    xcodebuild -project ./build/macosx/mapboxgl-app.xcodeproj
+    xcodebuild -project ./build/macosx/mapboxgl-app.xcodeproj -jobs 4
     #
     # build iOS
     #
-    git clone --depth 1 https://github.com/mapbox/mapbox-gl-cocoa ios/mapbox-gl-cocoa
+    git submodule init
+    git submodule update
     make iproj-cli
-    xcodebuild -project ./build/ios/mapbox-gl-cocoa/app/mapboxgl-app.xcodeproj -sdk iphonesimulator ONLY_ACTIVE_ARCH=NO
+    xcodebuild -project ./build/ios/mapbox-gl-cocoa/app/mapboxgl-app.xcodeproj -sdk iphonesimulator ONLY_ACTIVE_ARCH=NO -jobs 4
 fi
diff --git a/src/renderer/symbol_bucket.cpp b/src/renderer/symbol_bucket.cpp
index f953f0716..fd8931509 100644
--- a/src/renderer/symbol_bucket.cpp
+++ b/src/renderer/symbol_bucket.cpp
@@ -75,11 +75,10 @@ std::vector<SymbolFeature> SymbolBucket::processFeatures(const VectorTileLayer &
         if (text) {
             std::string u8string = util::replaceTokens(properties.text.field, feature.properties);
 
-            auto &convert = std::use_facet<std::ctype<char>>(std::locale());
             if (properties.text.transform == TextTransformType::Uppercase) {
-                convert.toupper(&u8string[0], &u8string[0] + u8string.size());
+                u8string = platform::uppercase(u8string);
             } else if (properties.text.transform == TextTransformType::Lowercase) {
-                convert.tolower(&u8string[0], &u8string[0] + u8string.size());
+                u8string = platform::lowercase(u8string);
             }
 
             ft.label = ucs4conv.convert(u8string);
diff --git a/test/test.gyp b/test/test.gyp
index 07709ecc8..fd7725bb0 100644
--- a/test/test.gyp
+++ b/test/test.gyp
@@ -201,6 +201,7 @@
             "./headless.cpp",
             "../common/headless_view.hpp",
             "../common/headless_view.cpp",
+            "../common/platform_default.cpp",
             "./fixtures/fixture_request.cpp",
             "./fixtures/fixture_log.hpp",
             "./fixtures/fixture_log.cpp",