diff --git a/CocoaSecurity.xcodeproj/project.xcworkspace/xcuserdata/Kelp.xcuserdatad/UserInterfaceState.xcuserstate b/CocoaSecurity.xcodeproj/project.xcworkspace/xcuserdata/Kelp.xcuserdatad/UserInterfaceState.xcuserstate
index ab4b992..f32879d 100644
Binary files a/CocoaSecurity.xcodeproj/project.xcworkspace/xcuserdata/Kelp.xcuserdatad/UserInterfaceState.xcuserstate and b/CocoaSecurity.xcodeproj/project.xcworkspace/xcuserdata/Kelp.xcuserdatad/UserInterfaceState.xcuserstate differ
diff --git a/CocoaSecurity/CocoaSecurity.h b/CocoaSecurity/CocoaSecurity.h
index b7ba4d1..3df0847 100644
--- a/CocoaSecurity/CocoaSecurity.h
+++ b/CocoaSecurity/CocoaSecurity.h
@@ -42,6 +42,9 @@
 
 #pragma mark - CocoaSecurity
 @interface CocoaSecurity : NSObject
+#pragma mark - Init
++ (id)sharedInstance;
+
 #pragma mark - AES Encrypt
 - (CocoaSecurityResult *)aesEncrypt:(NSString *)data key:(NSString *)key;
 - (CocoaSecurityResult *)aesEncrypt:(NSString *)data hexKey:(NSString *)key hexIv:(NSString *)iv;
diff --git a/CocoaSecurity/CocoaSecurity.m b/CocoaSecurity/CocoaSecurity.m
index ebfc0a1..5fd6f46 100644
--- a/CocoaSecurity/CocoaSecurity.m
+++ b/CocoaSecurity/CocoaSecurity.m
@@ -11,6 +11,17 @@
 #pragma mark - CocoaSecurity
 @implementation CocoaSecurity
 
+static CocoaSecurity *_instance = nil;
+
+#pragma mark - Init
++ (id)sharedInstance
+{
+    if (_instance == nil) {
+        _instance = [self new];
+    }
+    return _instance;
+}
+
 #pragma mark - AES Encrypt
 // default AES Encrypt, key -> SHA384(key).sub(0, 32), iv -> SHA384(key).sub(32, 16)
 - (CocoaSecurityResult *)aesEncrypt:(NSString *)data key:(NSString *)key
diff --git a/CocoaSecurityTests/CocoaSecurityTests.h b/CocoaSecurityTests/CocoaSecurityTests.h
index 00fd3dc..e14b071 100644
--- a/CocoaSecurityTests/CocoaSecurityTests.h
+++ b/CocoaSecurityTests/CocoaSecurityTests.h
@@ -3,7 +3,7 @@
 //  CocoaSecurityTests
 //
 //  Created by Kelp on 12/5/13.
-//  Copyright (c) 2012年 __MyCompanyName__. All rights reserved.
+//  Copyright (c) 2012 Phate. All rights reserved.
 //
 
 #import <SenTestingKit/SenTestingKit.h>
diff --git a/CocoaSecurityTests/CocoaSecurityTests.m b/CocoaSecurityTests/CocoaSecurityTests.m
index 1150da0..afdcb42 100644
--- a/CocoaSecurityTests/CocoaSecurityTests.m
+++ b/CocoaSecurityTests/CocoaSecurityTests.m
@@ -3,7 +3,7 @@
 //  CocoaSecurityTests
 //
 //  Created by Kelp on 12/5/13.
-//  Copyright (c) 2012年 __MyCompanyName__. All rights reserved.
+//  Copyright (c) 2012 Phate. All rights reserved.
 //
 
 #import "CocoaSecurityTests.h"
@@ -39,7 +39,7 @@
 
 - (void)testAES
 {
-    CocoaSecurity *cs = [[CocoaSecurity alloc] init];
+    CocoaSecurity *cs = [CocoaSecurity sharedInstance];
     CocoaSecurityDecoder *decoder = [[CocoaSecurityDecoder alloc] init];
     
     // AES128
@@ -78,7 +78,7 @@
 
 - (void)testMD5
 {
-    CocoaSecurity *cs = [[CocoaSecurity alloc] init];
+    CocoaSecurity *cs = [CocoaSecurity sharedInstance];
     CocoaSecurityResult *md5Result = [cs md5:@"kelp"];
     CocoaSecurityResult *hmacMd5Result = [cs hmacMd5:@"kelp" hmacKey:@"key"];
     
@@ -93,7 +93,7 @@
 
 - (void)testSHA
 {
-    CocoaSecurity *cs = [[CocoaSecurity alloc] init];
+    CocoaSecurity *cs = [CocoaSecurity sharedInstance];
     CocoaSecurityResult *sha1Result = [cs sha1:@"kelp"];
     CocoaSecurityResult *sha224Result = [cs sha224:@"kelp"];
     CocoaSecurityResult *sha256Result = [cs sha256:@"kelp"];