diff --git a/Android/MMKV/build.gradle b/Android/MMKV/build.gradle
index f6b5ef58..bdf5a2c8 100644
--- a/Android/MMKV/build.gradle
+++ b/Android/MMKV/build.gradle
@@ -1,7 +1,7 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.3.72'
+    ext.kotlin_version = '1.4.10'
 
     repositories {
         google()
diff --git a/Android/MMKV/gradle.properties b/Android/MMKV/gradle.properties
index 5c6a19db..e7b9e9d3 100644
--- a/Android/MMKV/gradle.properties
+++ b/Android/MMKV/gradle.properties
@@ -14,6 +14,6 @@ org.gradle.jvmargs=-Xmx1536m
 # http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
 # org.gradle.parallel=true
 
-VERSION_NAME_PREFIX=1.2.3
+VERSION_NAME_PREFIX=1.2.4
 #VERSION_NAME_SUFFIX=-SNAPSHOT
 VERSION_NAME_SUFFIX=
\ No newline at end of file
diff --git a/Android/MMKV/mmkv/build.gradle b/Android/MMKV/mmkv/build.gradle
index c3f83731..7518405f 100644
--- a/Android/MMKV/mmkv/build.gradle
+++ b/Android/MMKV/mmkv/build.gradle
@@ -1,8 +1,8 @@
 apply from: rootProject.file('gradle/build_library.gradle')
 
 android {
-//    defaultPublishConfig "StaticCppRelease"
-    defaultPublishConfig "SharedCppRelease"
+    defaultPublishConfig "StaticCppRelease"
+//    defaultPublishConfig "SharedCppRelease"
     defaultConfig {
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         externalNativeBuild {
diff --git a/Android/MMKV/mmkv/src/main/java/com/tencent/mmkv/MMKV.java b/Android/MMKV/mmkv/src/main/java/com/tencent/mmkv/MMKV.java
index f24b1fce..01abd003 100644
--- a/Android/MMKV/mmkv/src/main/java/com/tencent/mmkv/MMKV.java
+++ b/Android/MMKV/mmkv/src/main/java/com/tencent/mmkv/MMKV.java
@@ -98,9 +98,9 @@ public static String initialize(String rootDir, LibLoader loader, MMKVLogLevel l
             }
             System.loadLibrary("mmkv");
         }
+        jniInitialize(rootDir, logLevel2Int(logLevel));
         MMKV.rootDir = rootDir;
-        jniInitialize(MMKV.rootDir, logLevel2Int(logLevel));
-        return rootDir;
+        return MMKV.rootDir;
     }
 
     static private String rootDir = null;
diff --git a/Android/MMKV/mmkvdemo/build.gradle b/Android/MMKV/mmkvdemo/build.gradle
index b0a6d4fa..9587a8a2 100644
--- a/Android/MMKV/mmkvdemo/build.gradle
+++ b/Android/MMKV/mmkvdemo/build.gradle
@@ -82,8 +82,8 @@ repositories {
 dependencies {
     implementation fileTree(include: ['*.jar'], dir: 'libs')
     implementation project(':mmkv')
-//    implementation 'com.tencent:mmkv:1.2.3'
-//    implementation 'com.tencent:mmkv-static:1.2.3'
+//    implementation 'com.tencent:mmkv:1.2.4'
+//    implementation 'com.tencent:mmkv-static:1.2.4'
     implementation 'androidx.appcompat:appcompat:1.2.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.0.2'
     testImplementation 'junit:junit:4.12'
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1116f0e9..8198d82a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,14 @@
 # MMKV Change Log
 
+## v1.2.4 / 2020-10-21
+This is a hotfix mainly for iOS.
+
+### iOS / macOS
+* Fix a decode error of encrypted MMKV on some devices.
+
+### Android
+* Fix a potential issue on checking `rootDir` in multi-thread while MMKV initialization is not finished.
+
 ## v1.2.3 / 2020-10-16
 ### Changes for All platforms
 * Fix a potential crash on 32-bit devices due to pointer alignment issue.
diff --git a/Core/KeyValueHolder.cpp b/Core/KeyValueHolder.cpp
index 6bb5ab4a..638ae030 100644
--- a/Core/KeyValueHolder.cpp
+++ b/Core/KeyValueHolder.cpp
@@ -165,7 +165,7 @@ MMBuffer KeyValueHolderCrypt::toMMBuffer(const void *basePtr, const AESCrypt *cr
 
 } // namespace mmkv
 
-#if !defined(MMKV_DISABLE_CRYPT) && !defined(NDEBUG)
+#if !defined(MMKV_DISABLE_CRYPT) && defined(MMKV_DEBUG)
 #    include "CodedInputData.h"
 #    include "CodedOutputData.h"
 #    include "MMKVLog.h"
diff --git a/Core/KeyValueHolder.h b/Core/KeyValueHolder.h
index 6051581f..5f4cebf4 100644
--- a/Core/KeyValueHolder.h
+++ b/Core/KeyValueHolder.h
@@ -103,7 +103,7 @@ struct KeyValueHolderCrypt {
     explicit KeyValueHolderCrypt(const KeyValueHolderCrypt &other) = delete;
     KeyValueHolderCrypt &operator=(const KeyValueHolderCrypt &other) = delete;
 
-#ifndef NDEBUG
+#ifdef MMKV_DEBUG
     static void testAESToMMBuffer();
 #endif
 };
diff --git a/Core/MMKV.cpp b/Core/MMKV.cpp
index 75a28aab..7c8a7a64 100644
--- a/Core/MMKV.cpp
+++ b/Core/MMKV.cpp
@@ -179,7 +179,7 @@ void initialize() {
 #    endif // MMKV_USE_ARMV8_CRC32
 #endif     // __aarch64__ && defined(__linux__)
 
-#if !defined(NDEBUG) && !defined(MMKV_DISABLE_CRYPT)
+#if defined(MMKV_DEBUG) && !defined(MMKV_DISABLE_CRYPT)
     AESCrypt::testAESCrypt();
     KeyValueHolderCrypt::testAESToMMBuffer();
 #endif
diff --git a/Core/MMKVLog.cpp b/Core/MMKVLog.cpp
index 5747958a..34131148 100644
--- a/Core/MMKVLog.cpp
+++ b/Core/MMKVLog.cpp
@@ -22,7 +22,7 @@
 
 MMKV_NAMESPACE_BEGIN
 
-#ifndef NDEBUG
+#ifdef MMKV_DEBUG
 MMKVLogLevel g_currentLogLevel = MMKVLogDebug;
 #else
 MMKVLogLevel g_currentLogLevel = MMKVLogInfo;
diff --git a/Core/MMKVLog.h b/Core/MMKVLog.h
index f55f0ee9..5627ccdd 100644
--- a/Core/MMKVLog.h
+++ b/Core/MMKVLog.h
@@ -48,7 +48,7 @@ extern mmkv::LogHandler g_logHandler;
 #    define MMKVInfo(format, ...)                                                                                      \
         _MMKVLogWithLevel(MMKV_NAMESPACE_PREFIX::MMKVLogInfo, __FILE__, __func__, __LINE__, format, ##__VA_ARGS__)
 
-#    ifndef NDEBUG
+#    ifdef MMKV_DEBUG
 #        define MMKVDebug(format, ...)                                                                                 \
             _MMKVLogWithLevel(MMKV_NAMESPACE_PREFIX::MMKVLogDebug, __FILE__, __func__, __LINE__, format, ##__VA_ARGS__)
 #    else
diff --git a/Core/MMKVPredef.h b/Core/MMKVPredef.h
index 8579c44c..2f21b575 100755
--- a/Core/MMKVPredef.h
+++ b/Core/MMKVPredef.h
@@ -33,7 +33,15 @@
 #include <vector>
 #include <unordered_map>
 
-constexpr auto MMKV_VERSION = "v1.2.2";
+constexpr auto MMKV_VERSION = "v1.2.4";
+
+#ifdef DEBUG
+#    define MMKV_DEBUG
+#endif
+
+#ifdef NDEBUG
+#    undef MMKV_DEBUG
+#endif
 
 #ifdef __ANDROID__
 #    define MMKV_ANDROID
@@ -186,7 +194,7 @@ constexpr size_t AES_KEY_BITSET_LEN = 128;
 
 } // namespace mmkv
 
-#ifndef NDEBUG
+#ifdef MMKV_DEBUG
 #    include <cassert>
 #    define MMKV_ASSERT(var) assert(var)
 #else
diff --git a/Core/MiniPBCoder_OSX.cpp b/Core/MiniPBCoder_OSX.cpp
index 27a956dd..d6244102 100644
--- a/Core/MiniPBCoder_OSX.cpp
+++ b/Core/MiniPBCoder_OSX.cpp
@@ -136,7 +136,7 @@ void MiniPBCoder::decodeOneMap(MMKVMapCrypt &dic, size_t position, bool greedy)
             const auto &key = m_inputDataDecrpt->readString(kvHolder);
             if (key.length > 0) {
                 m_inputDataDecrpt->readData(kvHolder);
-                if (kvHolder.valueSize > 0) {
+                if (kvHolder.realValueSize() > 0) {
                     dictionary[key] = move(kvHolder);
                     [key retain];
                 } else {
diff --git a/Core/aes/AESCrypt.cpp b/Core/aes/AESCrypt.cpp
index b71e99b1..a7615602 100644
--- a/Core/aes/AESCrypt.cpp
+++ b/Core/aes/AESCrypt.cpp
@@ -163,7 +163,7 @@ AESCrypt AESCrypt::cloneWithStatus(const AESCryptStatus &status) const {
 
 } // namespace mmkv
 
-#    ifndef NDEBUG
+#    ifdef MMKV_DEBUG
 
 #        include "../MMKVLog.h"
 #        include "../MemoryFile.h"
@@ -252,5 +252,5 @@ void AESCrypt::testAESCrypt() {
 
 } // namespace mmkv
 
-#    endif // NDEBUG
+#    endif // MMKV_DEBUG
 #endif     // MMKV_DISABLE_CRYPT
diff --git a/Core/aes/AESCrypt.h b/Core/aes/AESCrypt.h
index e5b78dc0..0596f1c2 100644
--- a/Core/aes/AESCrypt.h
+++ b/Core/aes/AESCrypt.h
@@ -94,7 +94,7 @@ class AESCrypt {
 
     friend CodedInputDataCrypt;
 
-#ifndef NDEBUG
+#ifdef MMKV_DEBUG
     // check if AESCrypt is encrypt-decrypt full-duplex
     static void testAESCrypt();
 #endif
diff --git a/README.md b/README.md
index 05a258ce..6bc18b56 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 [![license](https://img.shields.io/badge/license-BSD_3-brightgreen.svg?style=flat)](https://github.com/Tencent/MMKV/blob/master/LICENSE.TXT)
 [![PRs Welcome](https://img.shields.io/badge/PRs-welcome-brightgreen.svg)](https://github.com/Tencent/MMKV/pulls)
-[![Release Version](https://img.shields.io/badge/release-1.2.3-brightgreen.svg)](https://github.com/Tencent/MMKV/releases)
+[![Release Version](https://img.shields.io/badge/release-1.2.4-brightgreen.svg)](https://github.com/Tencent/MMKV/releases)
 [![Platform](https://img.shields.io/badge/Platform-%20Android%20%7C%20iOS%2FmacOS%20%7C%20Win32%20%7C%20POSIX-brightgreen.svg)](https://github.com/Tencent/MMKV/wiki/home)
 
 中文版本请参看[这里](./readme_cn.md)
@@ -28,8 +28,8 @@ Add the following lines to `build.gradle` on your app module:
 
 ```gradle
 dependencies {
-    implementation 'com.tencent:mmkv-static:1.2.3'
-    // replace "1.2.3" with any available version
+    implementation 'com.tencent:mmkv-static:1.2.4'
+    // replace "1.2.4" with any available version
 }
 ```
 
diff --git a/iOS/MMKV/MMKV.xcodeproj/project.pbxproj b/iOS/MMKV/MMKV.xcodeproj/project.pbxproj
index a722a6bf..dde5693c 100644
--- a/iOS/MMKV/MMKV.xcodeproj/project.pbxproj
+++ b/iOS/MMKV/MMKV.xcodeproj/project.pbxproj
@@ -485,7 +485,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				MACOSX_DEPLOYMENT_TARGET = 10.9;
-				MARKETING_VERSION = 1.2.3;
+				MARKETING_VERSION = 1.2.4;
 				"OTHER_LDFLAGS[sdk=iphoneos*]" = (
 					"-framework",
 					UIKit,
@@ -531,7 +531,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				MACOSX_DEPLOYMENT_TARGET = 10.9;
-				MARKETING_VERSION = 1.2.3;
+				MARKETING_VERSION = 1.2.4;
 				"OTHER_LDFLAGS[sdk=iphoneos*]" = (
 					"-framework",
 					UIKit,
@@ -742,7 +742,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				MACOSX_DEPLOYMENT_TARGET = 10.9;
-				MARKETING_VERSION = 1.2.3;
+				MARKETING_VERSION = 1.2.4;
 				"OTHER_LDFLAGS[sdk=iphoneos*]" = (
 					"-framework",
 					UIKit,
@@ -782,7 +782,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				MACOSX_DEPLOYMENT_TARGET = 10.9;
-				MARKETING_VERSION = 1.2.3;
+				MARKETING_VERSION = 1.2.4;
 				"OTHER_LDFLAGS[sdk=iphoneos*]" = (
 					"-framework",
 					UIKit,
@@ -829,7 +829,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				MACOSX_DEPLOYMENT_TARGET = 10.9;
-				MARKETING_VERSION = 1.2.3;
+				MARKETING_VERSION = 1.2.4;
 				"OTHER_LDFLAGS[sdk=iphoneos*]" = (
 					"-framework",
 					UIKit,
@@ -878,7 +878,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				MACOSX_DEPLOYMENT_TARGET = 10.9;
-				MARKETING_VERSION = 1.2.3;
+				MARKETING_VERSION = 1.2.4;
 				"OTHER_LDFLAGS[sdk=iphoneos*]" = (
 					"-framework",
 					UIKit,
diff --git a/readme_cn.md b/readme_cn.md
index 4e94462d..a6f555bd 100644
--- a/readme_cn.md
+++ b/readme_cn.md
@@ -22,8 +22,8 @@ MMKV 是基于 mmap 内存映射的 key-value 组件，底层序列化/反序列
 
 ```gradle
 dependencies {
-    implementation 'com.tencent:mmkv-static:1.2.3'
-    // replace "1.2.3" with any available version
+    implementation 'com.tencent:mmkv-static:1.2.4'
+    // replace "1.2.4" with any available version
 }
 ```