diff --git a/armsrc/em4x70.c b/armsrc/em4x70.c
index 0ea6392d1..b1feb83b3 100644
--- a/armsrc/em4x70.c
+++ b/armsrc/em4x70.c
@@ -77,7 +77,7 @@ static int em4x70_receive(uint8_t *bits, size_t length);
 static bool find_listen_window(bool command);
 
 static void init_tag(void) {
-    memset(tag.data, 0x00, sizeof(tag.data) / sizeof(tag.data[0]));
+    memset(tag.data, 0x00, ARRAYLEN(tag.data));
 }
 
 static void em4x70_setup_read(void) {
diff --git a/client/android/pm3_main.c b/client/android/pm3_main.c
index 1fb1cc95f..74019b0cd 100644
--- a/client/android/pm3_main.c
+++ b/client/android/pm3_main.c
@@ -25,6 +25,7 @@
 #include "whereami.h"
 #include "comms.h"
 #include "fileutils.h"
+#include "commonutil.h"    // ARRAYLEN
 #include "jni_tools.h"
 
 //iceman, todo:  proxify socker server name.  Maybe set in preferences?
@@ -151,13 +152,13 @@ JNIEXPORT jint JNI_OnLoad(JavaVM *vm, void *reserved) {
         {"closePm3", "()V", ClosePm3}
     };
 
-    if ((*jniEnv)->RegisterNatives(jniEnv, clazz, methods, sizeof(methods) / sizeof(methods[0])) !=
+    if ((*jniEnv)->RegisterNatives(jniEnv, clazz, methods, ARRAYLEN(methods)) !=
             JNI_OK) {
         return -1;
     }
 
     if ((*jniEnv)->RegisterNatives(jniEnv, clz_test, methods1,
-                                   sizeof(methods1) / sizeof(methods1[0])) != JNI_OK) {
+                                   ARRAYLEN(methods1)) != JNI_OK) {
         return -1;
     }