diff --git a/tutorial02_prebuild_layers/app/src/main/jni/TutorialValLayer.cpp b/tutorial02_prebuild_layers/app/src/main/jni/TutorialValLayer.cpp
index c4464a0..35902b0 100644
--- a/tutorial02_prebuild_layers/app/src/main/jni/TutorialValLayer.cpp
+++ b/tutorial02_prebuild_layers/app/src/main/jni/TutorialValLayer.cpp
@@ -63,23 +63,23 @@ static VkBool32 VKAPI_PTR vkDebugReportCallbackEX_impl(
     uint64_t object, size_t location, int32_t messageCode,
     const char* pLayerPrefix, const char* pMessage, void* pUserData) {
   if (flags & VK_DEBUG_REPORT_INFORMATION_BIT_EXT) {
-    __android_log_print(ANDROID_LOG_INFO, "Vulkan Debug Message: ", "%s -- %s",
+    __android_log_print(ANDROID_LOG_INFO, "Vulkan-Debug-Message: ", "%s -- %s",
                         pLayerPrefix, pMessage);
   }
   if (flags & VK_DEBUG_REPORT_WARNING_BIT_EXT) {
-    __android_log_print(ANDROID_LOG_WARN, "Vulkan Debug Message: ", "%s -- %s",
+    __android_log_print(ANDROID_LOG_WARN, "Vulkan-Debug-Message: ", "%s -- %s",
                         pLayerPrefix, pMessage);
   }
   if (flags & VK_DEBUG_REPORT_PERFORMANCE_WARNING_BIT_EXT) {
-    __android_log_print(ANDROID_LOG_WARN, "Vulkan Debug Message (Perf): ",
+    __android_log_print(ANDROID_LOG_WARN, "Vulkan-Debug-Message-(Perf): ",
                         "%s -- %s", pLayerPrefix, pMessage);
   }
   if (flags & VK_DEBUG_REPORT_ERROR_BIT_EXT) {
-    __android_log_print(ANDROID_LOG_ERROR, "Vulkan Debug Message: ", "%s -- %s",
+    __android_log_print(ANDROID_LOG_ERROR, "Vulkan-Debug-Message: ", "%s -- %s",
                         pLayerPrefix, pMessage);
   }
   if (flags & VK_DEBUG_REPORT_DEBUG_BIT_EXT) {
-    __android_log_print(ANDROID_LOG_DEBUG, "Vulkan Debug Message: ", "%s -- %s",
+    __android_log_print(ANDROID_LOG_DEBUG, "Vulkan-Debug-Message: ", "%s -- %s",
                         pLayerPrefix, pMessage);
   }
 
diff --git a/tutorial03_traceable_layers/app/src/main/jni/TutorialValLayer.cpp b/tutorial03_traceable_layers/app/src/main/jni/TutorialValLayer.cpp
index e02fe11..f1b9d07 100644
--- a/tutorial03_traceable_layers/app/src/main/jni/TutorialValLayer.cpp
+++ b/tutorial03_traceable_layers/app/src/main/jni/TutorialValLayer.cpp
@@ -64,23 +64,23 @@ static VkBool32 VKAPI_PTR vkDebugReportCallbackEX_impl(
     uint64_t object, size_t location, int32_t messageCode,
     const char* pLayerPrefix, const char* pMessage, void* pUserData) {
   if (flags & VK_DEBUG_REPORT_INFORMATION_BIT_EXT) {
-    __android_log_print(ANDROID_LOG_INFO, "Vulkan Debug Message: ", "%s -- %s",
+    __android_log_print(ANDROID_LOG_INFO, "Vulkan-Debug-Message: ", "%s -- %s",
                         pLayerPrefix, pMessage);
   }
   if (flags & VK_DEBUG_REPORT_WARNING_BIT_EXT) {
-    __android_log_print(ANDROID_LOG_WARN, "Vulkan Debug Message: ", "%s -- %s",
+    __android_log_print(ANDROID_LOG_WARN, "Vulkan-Debug-Message: ", "%s -- %s",
                         pLayerPrefix, pMessage);
   }
   if (flags & VK_DEBUG_REPORT_PERFORMANCE_WARNING_BIT_EXT) {
-    __android_log_print(ANDROID_LOG_WARN, "Vulkan Debug Message (Perf): ",
+    __android_log_print(ANDROID_LOG_WARN, "Vulkan-Debug-Message-(Perf): ",
                         "%s -- %s", pLayerPrefix, pMessage);
   }
   if (flags & VK_DEBUG_REPORT_ERROR_BIT_EXT) {
-    __android_log_print(ANDROID_LOG_ERROR, "Vulkan Debug Message: ", "%s -- %s",
+    __android_log_print(ANDROID_LOG_ERROR, "Vulkan-Debug-Message: ", "%s -- %s",
                         pLayerPrefix, pMessage);
   }
   if (flags & VK_DEBUG_REPORT_DEBUG_BIT_EXT) {
-    __android_log_print(ANDROID_LOG_DEBUG, "Vulkan Debug Message: ", "%s -- %s",
+    __android_log_print(ANDROID_LOG_DEBUG, "Vulkan-Debug-Message: ", "%s -- %s",
                         pLayerPrefix, pMessage);
   }
 
diff --git a/tutorial05_triangle/app/src/main/jni/VulkanMain.cpp b/tutorial05_triangle/app/src/main/jni/VulkanMain.cpp
index c1aa12a..8aa64f7 100644
--- a/tutorial05_triangle/app/src/main/jni/VulkanMain.cpp
+++ b/tutorial05_triangle/app/src/main/jni/VulkanMain.cpp
@@ -377,14 +377,14 @@ bool CreateBuffers(void) {
   VkMemoryAllocateInfo allocInfo{
       .sType = VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO,
       .pNext = nullptr,
-      .allocationSize = sizeof(vertexData),
+      .allocationSize = memReq.size,
       .memoryTypeIndex = 0,  // Memory type assigned in the next step
   };
 
   // Assign the proper memory type for that buffer
-  allocInfo.allocationSize = memReq.size;
   MapMemoryTypeToIndex(memReq.memoryTypeBits,
-                       VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT,
+                       VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT |
+                       VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
                        &allocInfo.memoryTypeIndex);
 
   // Allocate memory for the buffer
@@ -392,8 +392,8 @@ bool CreateBuffers(void) {
   CALL_VK(vkAllocateMemory(device.device_, &allocInfo, nullptr, &deviceMemory));
 
   void* data;
-  CALL_VK(vkMapMemory(device.device_, deviceMemory, 0, sizeof(vertexData), 0,
-                      &data));
+  CALL_VK(vkMapMemory(device.device_, deviceMemory, 0, allocInfo.allocationSize,
+                      0, &data));
   memcpy(data, vertexData, sizeof(vertexData));
   vkUnmapMemory(device.device_, deviceMemory);
 
@@ -418,6 +418,7 @@ VkResult loadShaderFromFile(const char* filePath, VkShaderModule* shaderOut,
   char* fileContent = new char[fileLength];
 
   AAsset_read(file, fileContent, fileLength);
+  AAsset_close(file);
 
   VkShaderModuleCreateInfo shaderModuleCreateInfo{
       .sType = VK_STRUCTURE_TYPE_SHADER_MODULE_CREATE_INFO,
diff --git a/tutorial06_texture/app/src/main/cpp/VulkanMain.cpp b/tutorial06_texture/app/src/main/cpp/VulkanMain.cpp
index d0197d6..20d6f52 100644
--- a/tutorial06_texture/app/src/main/cpp/VulkanMain.cpp
+++ b/tutorial06_texture/app/src/main/cpp/VulkanMain.cpp
@@ -401,6 +401,7 @@ VkResult LoadTextureFromFile(const char* filePath,
   size_t fileLength = AAsset_getLength(file);
   stbi_uc* fileContent = new unsigned char[fileLength];
   AAsset_read(file, fileContent, fileLength);
+  AAsset_close(file);
 
   uint32_t imgWidth, imgHeight, n;
   unsigned char* imageData = stbi_load_from_memory(
@@ -702,14 +703,14 @@ bool CreateBuffers(void) {
   VkMemoryAllocateInfo allocInfo{
       .sType = VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO,
       .pNext = nullptr,
-      .allocationSize = sizeof(vertexData),
+      .allocationSize = memReq.size,
       .memoryTypeIndex = 0,  // Memory type assigned in the next step
   };
 
   // Assign the proper memory type for that buffer
-  allocInfo.allocationSize = memReq.size;
   MapMemoryTypeToIndex(memReq.memoryTypeBits,
-                       VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT,
+                       VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT |
+                       VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
                        &allocInfo.memoryTypeIndex);
 
   // Allocate memory for the buffer
@@ -717,8 +718,8 @@ bool CreateBuffers(void) {
   CALL_VK(vkAllocateMemory(device.device_, &allocInfo, nullptr, &deviceMemory));
 
   void* data;
-  CALL_VK(vkMapMemory(device.device_, deviceMemory, 0, sizeof(vertexData), 0,
-                      &data));
+  CALL_VK(vkMapMemory(device.device_, deviceMemory, 0, allocInfo.allocationSize,
+                      0, &data));
   memcpy(data, vertexData, sizeof(vertexData));
   vkUnmapMemory(device.device_, deviceMemory);