diff --git a/include/hardware/bt_gatt_client.h b/include/hardware/bt_gatt_client.h
index e2c8a92..86991b1 100644
--- a/include/hardware/bt_gatt_client.h
+++ b/include/hardware/bt_gatt_client.h
@@ -19,9 +19,12 @@
 #define ANDROID_INCLUDE_BT_GATT_CLIENT_H
 
 #include <stdint.h>
+#include <vector>
 #include "bt_gatt_types.h"
 #include "bt_common_types.h"
 
+using std::vector;
+
 __BEGIN_DECLS
 
 /**
@@ -304,16 +307,16 @@
 
     /** Write a remote characteristic */
     bt_status_t (*write_characteristic)(int conn_id, uint16_t handle,
-                    int write_type, int len, int auth_req,
-                    char* p_value);
+                    int write_type, int auth_req,
+                    vector<uint8_t> value);
 
     /** Read the descriptor for a given characteristic */
     bt_status_t (*read_descriptor)(int conn_id, uint16_t handle, int auth_req);
 
     /** Write a remote descriptor for a given characteristic */
     bt_status_t (*write_descriptor)( int conn_id, uint16_t handle,
-                    int write_type, int len,
-                    int auth_req, char* p_value);
+                    int write_type, int auth_req,
+                    vector<uint8_t> value);
 
     /** Execute a prepared write operation */
     bt_status_t (*execute_write)(int conn_id, int execute);
diff --git a/include/hardware/bt_gatt_server.h b/include/hardware/bt_gatt_server.h
index 0d6cc1e..d2fdda3 100644
--- a/include/hardware/bt_gatt_server.h
+++ b/include/hardware/bt_gatt_server.h
@@ -19,9 +19,12 @@
 #define ANDROID_INCLUDE_BT_GATT_SERVER_H
 
 #include <stdint.h>
+#include <vector>
 
 #include "bt_gatt_types.h"
 
+using std::vector;
+
 __BEGIN_DECLS
 
 /** GATT value type used in response to remote read requests */
@@ -182,8 +185,8 @@
 
     /** Send value indication to a remote device */
     bt_status_t (*send_indication)(int server_if, int attribute_handle,
-                                   int conn_id, int len, int confirm,
-                                   char* p_value);
+                                   int conn_id, int confirm,
+                                   vector<uint8_t> value);
 
     /** Send a response to a read/write operation */
     bt_status_t (*send_response)(int conn_id, int trans_id,