Adding -Ofast for sample build.
diff --git a/samples/hello-oboe/CMakeLists.txt b/samples/hello-oboe/CMakeLists.txt
index 50136a0..be7f3fd 100644
--- a/samples/hello-oboe/CMakeLists.txt
+++ b/samples/hello-oboe/CMakeLists.txt
@@ -53,3 +53,9 @@
 
 # Specify the libraries needed for hello-oboe
 target_link_libraries(hello-oboe android log oboe)
+
+# Enable optimization for release build; it could be enabled for debug build
+# if performance is of interest.
+target_compile_options(hello-oboe
+    PRIVATE
+        -std=c++14 -Wall -Werror $<$<CONFIG:RELEASE>:-Ofast>)