diff --git a/native-activity/app/src/main/cpp/main.cpp b/native-activity/app/src/main/cpp/main.cpp
index 2f82d570d..dd774849f 100644
--- a/native-activity/app/src/main/cpp/main.cpp
+++ b/native-activity/app/src/main/cpp/main.cpp
@@ -77,7 +77,7 @@ struct SavedState {
  * Shared state for our app.
  */
 struct Engine {
-  struct android_app* app;
+  android_app* app;
 
   ASensorManager* sensorManager;
   const ASensor* accelerometerSensor;
@@ -89,7 +89,7 @@ struct Engine {
   EGLContext context;
   int32_t width;
   int32_t height;
-  struct SavedState state;
+  SavedState state;
 
   void CreateSensorListener(ALooper_callbackFunc callback) {
     CHECK_NOT_NULL(app);
@@ -109,7 +109,7 @@ struct Engine {
 /**
  * Initialize an EGL context for the current display.
  */
-static int engine_init_display(struct Engine* engine) {
+static int engine_init_display(Engine* engine) {
   // initialize OpenGL ES and EGL
 
   /*
@@ -209,7 +209,7 @@ static int engine_init_display(struct Engine* engine) {
 /**
  * Just the current frame in the display.
  */
-static void engine_draw_frame(struct Engine* engine) {
+static void engine_draw_frame(Engine* engine) {
   if (engine->display == nullptr) {
     // No display.
     return;
@@ -226,7 +226,7 @@ static void engine_draw_frame(struct Engine* engine) {
 /**
  * Tear down the EGL context currently associated with the display.
  */
-static void engine_term_display(struct Engine* engine) {
+static void engine_term_display(Engine* engine) {
   if (engine->display != EGL_NO_DISPLAY) {
     eglMakeCurrent(engine->display, EGL_NO_SURFACE, EGL_NO_SURFACE,
                    EGL_NO_CONTEXT);
@@ -247,9 +247,9 @@ static void engine_term_display(struct Engine* engine) {
 /**
  * Process the next input event.
  */
-static int32_t engine_handle_input(struct android_app* app,
+static int32_t engine_handle_input(android_app* app,
                                    AInputEvent* event) {
-  auto* engine = (struct Engine*)app->userData;
+  auto* engine = (Engine*)app->userData;
   if (AInputEvent_getType(event) == AINPUT_EVENT_TYPE_MOTION) {
     engine->animating = 1;
     engine->state.x = AMotionEvent_getX(event, 0);
@@ -262,14 +262,14 @@ static int32_t engine_handle_input(struct android_app* app,
 /**
  * Process the next main command.
  */
-static void engine_handle_cmd(struct android_app* app, int32_t cmd) {
-  auto* engine = (struct Engine*)app->userData;
+static void engine_handle_cmd(android_app* app, int32_t cmd) {
+  auto* engine = (Engine*)app->userData;
   switch (cmd) {
     case APP_CMD_SAVE_STATE:
       // The system has asked us to save our current state.  Do so.
-      engine->app->savedState = malloc(sizeof(struct SavedState));
-      *((struct SavedState*)engine->app->savedState) = engine->state;
-      engine->app->savedStateSize = sizeof(struct SavedState);
+      engine->app->savedState = malloc(sizeof(SavedState));
+      *((SavedState*)engine->app->savedState) = engine->state;
+      engine->app->savedStateSize = sizeof(SavedState);
       break;
     case APP_CMD_INIT_WINDOW:
       // The window is being shown, get it ready.
@@ -311,7 +311,7 @@ static void engine_handle_cmd(struct android_app* app, int32_t cmd) {
 
 int OnSensorEvent(int /* fd */, int /* events */, void* data) {
   CHECK_NOT_NULL(data);
-  Engine* engine = reinterpret_cast<struct Engine*>(data);
+  Engine* engine = reinterpret_cast<Engine*>(data);
 
   CHECK_NOT_NULL(engine->accelerometerSensor);
   ASensorEvent event;
@@ -332,8 +332,8 @@ int OnSensorEvent(int /* fd */, int /* events */, void* data) {
  * android_native_app_glue.  It runs in its own thread, with its own
  * event loop for receiving input events and doing other things.
  */
-void android_main(struct android_app* state) {
-  struct Engine engine {};
+void android_main(android_app* state) {
+  Engine engine {};
 
   memset(&engine, 0, sizeof(engine));
   state->userData = &engine;
@@ -346,7 +346,7 @@ void android_main(struct android_app* state) {
 
   if (state->savedState != nullptr) {
     // We are starting with a previous saved state; restore from it.
-    engine.state = *(struct SavedState*)state->savedState;
+    engine.state = *(SavedState*)state->savedState;
   }
 
   // loop waiting for stuff to do.
@@ -354,7 +354,7 @@ void android_main(struct android_app* state) {
   while (true) {
     // Read all pending events.
     int events;
-    struct android_poll_source* source;
+    android_poll_source* source;
 
     // If not animating, we will block forever waiting for events.
     // If animating, we loop until all events are read, then continue