diff --git a/APAddressBook.xcodeproj/project.pbxproj b/APAddressBook.xcodeproj/project.pbxproj
index 07c4b3c..49a27ea 100644
--- a/APAddressBook.xcodeproj/project.pbxproj
+++ b/APAddressBook.xcodeproj/project.pbxproj
@@ -361,7 +361,7 @@
 		CD189A281E9D39D1009CDF82 /* Project object */ = {
 			isa = PBXProject;
 			attributes = {
-				LastUpgradeCheck = 0810;
+				LastUpgradeCheck = 0900;
 				ORGANIZATIONNAME = Alterplay;
 				TargetAttributes = {
 					CD189A301E9D39D1009CDF82 = {
@@ -440,7 +440,9 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
 				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
@@ -448,7 +450,12 @@
 				CLANG_WARN_ENUM_CONVERSION = YES;
 				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_SUSPICIOUS_MOVES = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
@@ -493,7 +500,9 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
 				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
@@ -501,7 +510,12 @@
 				CLANG_WARN_ENUM_CONVERSION = YES;
 				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_SUSPICIOUS_MOVES = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
diff --git a/APAddressBook.xcodeproj/project.xcworkspace/contents.xcworkspacedata b/APAddressBook.xcodeproj/project.xcworkspace/contents.xcworkspacedata
new file mode 100644
index 0000000..919434a
--- /dev/null
+++ b/APAddressBook.xcodeproj/project.xcworkspace/contents.xcworkspacedata
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "self:">
+   </FileRef>
+</Workspace>
diff --git a/APAddressBook.xcodeproj/xcshareddata/xcschemes/APAddressBook.xcscheme b/APAddressBook.xcodeproj/xcshareddata/xcschemes/APAddressBook.xcscheme
index 809139f..b427845 100644
--- a/APAddressBook.xcodeproj/xcshareddata/xcschemes/APAddressBook.xcscheme
+++ b/APAddressBook.xcodeproj/xcshareddata/xcschemes/APAddressBook.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0810"
+   LastUpgradeVersion = "0900"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -26,6 +26,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       shouldUseLaunchSchemeArgsEnv = "YES">
       <Testables>
       </Testables>
@@ -36,6 +37,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"
diff --git a/Pod/Core/Private/Thread/APThread.h b/Pod/Core/Private/Thread/APThread.h
index 8fcc860..fa7389d 100644
--- a/Pod/Core/Private/Thread/APThread.h
+++ b/Pod/Core/Private/Thread/APThread.h
@@ -10,7 +10,7 @@
 
 @interface APThread : NSThread
 
-- (void)dispatchAsync:(void (^)())block;
-- (void)dispatchSync:(void (^)())block;
+- (void)dispatchAsync:(void (^)(void))block;
+- (void)dispatchSync:(void (^)(void))block;
 
-@end
\ No newline at end of file
+@end
diff --git a/Pod/Core/Private/Thread/APThread.m b/Pod/Core/Private/Thread/APThread.m
index 88c203b..8021de9 100644
--- a/Pod/Core/Private/Thread/APThread.m
+++ b/Pod/Core/Private/Thread/APThread.m
@@ -12,12 +12,12 @@ @implementation APThread
 
 #pragma mark - public
 
-- (void)dispatchAsync:(void (^)())block
+- (void)dispatchAsync:(void (^)(void))block
 {
     [self performSelector:@selector(performBlock:) onThread:self withObject:block waitUntilDone:NO];
 }
 
-- (void)dispatchSync:(void (^)())block
+- (void)dispatchSync:(void (^)(void))block
 {
     [self performSelector:@selector(performBlock:) onThread:self withObject:block waitUntilDone:YES];
 }
@@ -38,9 +38,9 @@ - (void)main
 
 #pragma mark - private
 
-- (void)performBlock:(void (^)())block
+- (void)performBlock:(void (^)(void))block
 {
     block();
 }
 
-@end
\ No newline at end of file
+@end
diff --git a/Pod/Core/Public/APAddressBook.h b/Pod/Core/Public/APAddressBook.h
index c903b75..3a7bd5b 100755
--- a/Pod/Core/Public/APAddressBook.h
+++ b/Pod/Core/Public/APAddressBook.h
@@ -32,12 +32,12 @@
 - (void)loadPhotoByRecordID:(nonnull NSNumber *)recordID
                     onQueue:(nonnull dispatch_queue_t)queue
                  completion:(nonnull void (^)(UIImage * _Nullable photo))completion;
-- (void)startObserveChangesWithCallback:(nonnull void (^)())callback;
+- (void)startObserveChangesWithCallback:(nonnull void (^)(void))callback;
 - (void)startObserveChangesOnQueue:(nonnull dispatch_queue_t)queue
-                          callback:(nonnull void (^)())callback;
+                          callback:(nonnull void (^)(void))callback;
 - (void)stopObserveChanges;
 - (void)requestAccess:(nonnull void (^)(BOOL granted, NSError * _Nullable error))completionBlock;
 - (void)requestAccessOnQueue:(nonnull dispatch_queue_t)queue
                   completion:(nonnull void (^)(BOOL granted, NSError * _Nullable error))completionBlock;
 
-@end
\ No newline at end of file
+@end
diff --git a/Pod/Core/Public/APAddressBook.m b/Pod/Core/Public/APAddressBook.m
index 1eea38d..8577953 100755
--- a/Pod/Core/Public/APAddressBook.m
+++ b/Pod/Core/Public/APAddressBook.m
@@ -19,7 +19,7 @@ @interface APAddressBook () <APAddressBookExternalChangeDelegate>
 @property (nonatomic, strong) APAddressBookContactsRoutine *contacts;
 @property (nonatomic, strong) APAddressBookExternalChangeRoutine *externalChange;
 @property (nonatomic, strong) APThread *thread;
-@property (atomic, copy) void (^externalChangeCallback)();
+@property (atomic, copy) void (^externalChangeCallback)(void);
 @property (atomic, strong) dispatch_queue_t externalChangeQueue;
 @end
 
@@ -130,12 +130,12 @@ - (void)loadPhotoByRecordID:(NSNumber *)recordID onQueue:(dispatch_queue_t)queue
     }];
 }
 
-- (void)startObserveChangesWithCallback:(void (^)())callback
+- (void)startObserveChangesWithCallback:(void (^)(void))callback
 {
     [self startObserveChangesOnQueue:dispatch_get_main_queue() callback:callback];
 }
 
-- (void)startObserveChangesOnQueue:(dispatch_queue_t)queue callback:(void (^)())callback
+- (void)startObserveChangesOnQueue:(dispatch_queue_t)queue callback:(void (^)(void))callback
 {
     self.externalChangeCallback = callback;
     self.externalChangeQueue = queue;