diff --git a/config/rel_slices.yml b/config/rel_slices.yml
index 1dc5a17e..84f81a81 100644
--- a/config/rel_slices.yml
+++ b/config/rel_slices.yml
@@ -9,6 +9,9 @@ m_debug_hayakawa.c:
     .text: [0x803965E4, 0x803973E8]
     .rodata: [0x80641D50, 0x80641D90]
     .data: [0x80651328, 0x80651358]
+m_eappli.c:
+    .text: [0x8039A5E0, 0x8039A960]
+    .bss: [0x81295150, 0x81295550]
 m_fbdemo.c:
     .text: [0x803A0350, 0x803A0ABC]
     .rodata: [0x80641F40, 0x80641F60]
diff --git a/include/libjsys/jsyswrapper.h b/include/libjsys/jsyswrapper.h
index 692a487e..b29d2a01 100644
--- a/include/libjsys/jsyswrapper.h
+++ b/include/libjsys/jsyswrapper.h
@@ -9,12 +9,18 @@
 extern "C" {
 #endif
 
+enum resource_index {
+  /* TODO: finish */
+  RESOURCE_MY_ORIGINAL = 27,
+};
+
 extern void JW_Init();
 extern void JW_Init2();
 extern void* JW_Alloc(size_t size, int align);
 extern void JW_Free(void* ptr);
 extern s32 JW_Resize(void* ptr, size_t new_size);
 extern size_t JW_GetMemBlockSize(void* ptr);
+extern size_t JW_GetResSizeFileNo(int file_no);
 extern void JW_BeginFrame();
 extern void JW_EndFrame();
 extern void JW_JUTReport(int x, int y, int show_count, const char* fmt, ...);
diff --git a/include/m_eappli.h b/include/m_eappli.h
new file mode 100644
index 00000000..740a44e2
--- /dev/null
+++ b/include/m_eappli.h
@@ -0,0 +1,16 @@
+#ifndef M_EAPPLI_H
+#define M_EAPPLI_H
+
+#include "types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/include/m_malloc.h b/include/m_malloc.h
index 5ee359d0..5c7acfb9 100644
--- a/include/m_malloc.h
+++ b/include/m_malloc.h
@@ -10,15 +10,15 @@ extern "C" {
 
 extern Arena zelda_arena; 
 
-extern void zelda_malloc_align(u32,u32);
-extern void zelda_malloc(u32);
-extern void zelda_malloc_r(u32);
+extern void* zelda_malloc_align(size_t,u32);
+extern void* zelda_malloc(size_t);
+extern void* zelda_malloc_r(size_t);
 extern void zelda_free(void*);
 extern void zelda_GetFreeArena(size_t* max, size_t* free, size_t* alloc);
-extern u32 zelda_GetTotalFreeSize(void);
-extern u32 zelda_GetMemBlockSize(void*);
-extern void zelda_InitArena(void*, u32);
-extern void zelda_AddBlockArena(void*, u32);
+extern size_t zelda_GetTotalFreeSize(void);
+extern size_t zelda_GetMemBlockSize(void*);
+extern void zelda_InitArena(void*, size_t);
+extern void zelda_AddBlockArena(void*, size_t);
 extern void zelda_CleanupArena(void);
 extern int zelda_MallocIsInitalized();
 
diff --git a/include/m_private.h b/include/m_private.h
index 90ce0670..39e64418 100644
--- a/include/m_private.h
+++ b/include/m_private.h
@@ -28,6 +28,9 @@ enum {
   mPr_PLAYER_NUM
 };
 
+#define mPr_ECARD_NUM 367
+#define mPr_ECARD_LETTER_NUM ((mPr_ECARD_NUM + 7) / 8) // 46
+
 #define mPr_POCKETS_SLOT_COUNT 15
 #define mPr_INVENTORY_MAIL_COUNT 10
 #define mPr_DELIVERY_QUEST_NUM mPr_POCKETS_SLOT_COUNT
@@ -95,7 +98,7 @@ typedef struct player_sunburn_s {
 /* sizeof(mPr_carde_data_c) == 0x32 */
 typedef struct player_ecard_data_s {
   /* 0x00 */ lbRTC_ymd_t letter_send_date; /* date the latest eCard letter was sent */
-  /* 0x04 */ u8 card_letters_sent[46]; /* bitfield keeping track of which eCard letters have been sent to the player [0, 366] */
+  /* 0x04 */ u8 card_letters_sent[mPr_ECARD_LETTER_NUM]; /* bitfield keeping track of which eCard letters have been sent to the player [0, 366] */
 } mPr_carde_data_c;
 
 typedef struct private_s {
diff --git a/rel/m_eappli.c b/rel/m_eappli.c
new file mode 100644
index 00000000..700af571
--- /dev/null
+++ b/rel/m_eappli.c
@@ -0,0 +1,136 @@
+#include "m_eappli.h"
+
+#include "m_common_data.h"
+#include "m_private.h"
+#include "lb_rtc.h"
+#include "m_scene.h"
+#include "m_malloc.h"
+#include "libjsys/jsyswrapper.h"
+
+#define CRC32_POLYNOMIAL 0xEDB88320
+#define CRC32_START_VALUE 0xAA478422
+
+static u32 crcTable[256];
+
+static u32 getcrc(u8* data, size_t len) {
+  u32 crc = CRC32_START_VALUE;
+  size_t i = 0;
+
+  do {
+    crc = (crc >> 8) ^ crcTable[(crc ^ data[i]) & 0xFF];
+    i++;
+  } while (i != len);
+
+  return crc;
+}
+
+static void crcgen() {
+  int bit;
+  u32 c;
+  int i;
+
+  for (i = 0; i < 256; i++) {
+    int j;
+    c = i;
+    
+    for (j = 0; j < 8; j++) {
+      bit = c & 1;
+      c >>= 1;
+      if (bit) {
+        c ^= CRC32_POLYNOMIAL;
+      }
+    }
+
+    crcTable[i] = c;
+  }
+}
+
+static u32 mEA_GetCRC(u8* data, size_t len) {
+  crcgen();
+  return getcrc(data, len);
+}
+
+static void putLEWord(u8* dst, u32 word) {
+  dst[0] = word >>  0;
+  dst[1] = word >>  8;
+  dst[2] = word >> 16;
+  dst[3] = word >> 24;
+}
+
+extern void mEA_InitLetterCardE() {
+  mPr_carde_data_c* carde_data = &Common_Get(now_private)->ecard_letter_data;
+  lbRTC_time_c* rtc_time = Common_GetPointer(time.rtc_time);
+
+  /* only reset if current date isn't same as last scan date */
+  u16 year = carde_data->letter_send_date.year;
+  u8 month = carde_data->letter_send_date.month;
+  u8 day = carde_data->letter_send_date.day;
+  if (rtc_time->year != year || rtc_time->month != month || rtc_time->day != day) {
+    int i;
+    for (i = 0; i < mPr_ECARD_LETTER_NUM; i++) {
+      carde_data->card_letters_sent[i] = 0;
+    }
+  }
+}
+
+extern int mEA_CheckLetterCardE(int card_no) {
+  mPr_carde_data_c* card_data = &Common_Get(now_private)->ecard_letter_data;
+  int index = card_no < mPr_ECARD_NUM ? card_no : mPr_ECARD_NUM - 1;
+
+  if (index == mPr_ECARD_NUM - 1) {
+    return ((card_data->card_letters_sent[index >> 3] >> (index & 7)) & 1) ? 2 : 0;
+  }
+
+  return (card_data->card_letters_sent[index >> 3] >> (index & 7)) & 1;
+}
+
+extern void mEA_SetLetterCardE(int card_no) {
+  mPr_carde_data_c* card_data = &Common_Get(now_private)->ecard_letter_data;
+  int index = card_no < mPr_ECARD_NUM ? card_no : mPr_ECARD_NUM - 1;
+  lbRTC_time_c* rtc_time = Common_GetPointer(time.rtc_time);
+
+  card_data->card_letters_sent[index >> 3] |= 1 << (index & 7);
+  card_data->letter_send_date.year = rtc_time->year;
+  card_data->letter_send_date.month = rtc_time->month;
+  card_data->letter_send_date.day = rtc_time->day;
+}
+
+#define MY_ORIGINAL_DESIGN_DATA_SIZE (4*(32/2)*32)
+extern void mEA_GetCardDLProgram() {
+  if (Save_Get(scene_no) != SCENE_TITLE_DEMO && Common_Get(carde_program_p) == NULL) {
+    u32 crc;
+      
+    Common_Set(carde_program_size, JW_GetResSizeFileNo(RESOURCE_MY_ORIGINAL) - MY_ORIGINAL_DESIGN_DATA_SIZE); // my_original.bin also contains texture data
+    Common_Set(carde_program_p, (u8*)zelda_malloc_align(Common_Get(carde_program_size), 32));
+    _JW_GetResourceAram(JW_GetAramAddress(RESOURCE_MY_ORIGINAL) + MY_ORIGINAL_DESIGN_DATA_SIZE, Common_Get(carde_program_p), Common_Get(carde_program_size));
+    
+    /* write compressed program size to vpk payload */
+    putLEWord(
+      Common_Get(carde_program_p) + 0x2C,
+      Common_Get(carde_program_size) - 0x34
+    );
+
+    /* write vpk CRC32 */
+    crc = mEA_GetCRC(Common_Get(carde_program_p) + sizeof(u32), Common_Get(carde_program_size) - sizeof(u32));
+    putLEWord(
+      Common_Get(carde_program_p),
+      crc
+    );
+  }
+}
+
+extern void mEA_CleanCardDLProgram() {
+  if (Common_Get(carde_program_p) != NULL) {
+    zelda_free(Common_Get(carde_program_p));
+    Common_Set(carde_program_p, NULL);
+    Common_Set(carde_program_size, 0);
+  }
+}
+
+extern u8* mEA_dl_carde_program_p() {
+  return Common_Get(carde_program_p);
+}
+
+extern size_t mEA_dl_carde_program_size() {
+  return Common_Get(carde_program_size);
+}
diff --git a/rel/m_malloc.c b/rel/m_malloc.c
index 7cd3d4f3..4899d6ab 100644
--- a/rel/m_malloc.c
+++ b/rel/m_malloc.c
@@ -2,45 +2,45 @@
 
 Arena zelda_arena;
 
-void zelda_malloc_align(u32 size, u32 align){
-    __osMallocAlign(&zelda_arena, size, align);
+extern void* zelda_malloc_align(size_t size, u32 align) {
+  return __osMallocAlign(&zelda_arena, size, align);
 }
 
-void zelda_malloc(u32 size){
-    __osMalloc(&zelda_arena,size);
+extern void* zelda_malloc(size_t size) {
+  return __osMalloc(&zelda_arena,size);
 }
 
-void zelda_malloc_r(u32 size){
-    __osMallocR(&zelda_arena, size);
+extern void* zelda_malloc_r(size_t size) {
+  return __osMallocR(&zelda_arena, size);
 }
 
-void zelda_free(void* ptr){
-    __osFree(&zelda_arena, ptr);
+extern void zelda_free(void* ptr) {
+  __osFree(&zelda_arena, ptr);
 }
 
-void zelda_GetFreeArena(size_t* max, size_t* free, size_t* alloc){
-    __osGetFreeArena(&zelda_arena,max,free,alloc);
+extern void zelda_GetFreeArena(size_t* max, size_t* free, size_t* alloc) {
+  __osGetFreeArena(&zelda_arena,max,free,alloc);
 }
 
-size_t zelda_GetTotalFreeSize(void){
-    return __osGetTotalFreeSize(&zelda_arena);
+extern size_t zelda_GetTotalFreeSize(void) {
+  return __osGetTotalFreeSize(&zelda_arena);
 }
 
-size_t zelda_GetMemBlockSize(void* ptr){
-    return __osGetMemBlockSize(&zelda_arena, ptr);
+extern size_t zelda_GetMemBlockSize(void* ptr) {
+  return __osGetMemBlockSize(&zelda_arena, ptr);
 }
 
-void zelda_InitArena(void* start, u32 size){
-    __osMallocInit(&zelda_arena, start, size);
+extern void zelda_InitArena(void* start, size_t size) {
+  __osMallocInit(&zelda_arena, start, size);
 }
-void zelda_AddBlockArena(void* start, u32 size){
-    __osMallocAddBlock(&zelda_arena,start, size);
+extern void zelda_AddBlockArena(void* start, size_t size) {
+  __osMallocAddBlock(&zelda_arena,start, size);
 }
 
-void zelda_CleanupArena() {
-    __osMallocCleanup(&zelda_arena);
+extern void zelda_CleanupArena() {
+  __osMallocCleanup(&zelda_arena);
 }
 
 extern int zelda_MallocIsInitalized() {
-    return __osMallocIsInitalized(&zelda_arena);
+  return __osMallocIsInitalized(&zelda_arena);
 }