diff --git a/Makefile b/Makefile
index 8607d6d..7056290 100644
--- a/Makefile
+++ b/Makefile
@@ -66,3 +66,6 @@ monitor1:
 
 monitor2:
 	idf.py monitor -p /dev/ttyUSB2
+
+flash_second_ota:
+	parttool.py --port /dev/ttyACM0 write_partition --partition-name="ota_1" --input build/espAlox.bin
diff --git a/main/ota_update.c b/main/ota_update.c
index c86b96e..2b35912 100644
--- a/main/ota_update.c
+++ b/main/ota_update.c
@@ -1,6 +1,7 @@
 #include "ota_update.h"
 #include "communication_handler.h"
 #include "driver/uart.h"
+#include "esp_app_format.h"
 #include "esp_log.h"
 #include "esp_ota_ops.h"
 #include "esp_partition.h"
@@ -26,6 +27,32 @@ static uint16_t current_block_id;
 static uint16_t update_buffer_write_index;
 static uint32_t update_size;
 static uint16_t sequenz_counter; // how often the update buffer gets written
+
+u_int32_t get_app_size(const esp_partition_t *app_size_partition) {
+  esp_app_desc_t app_desc;
+  esp_ota_get_partition_description(app_size_partition, &app_desc);
+
+  esp_image_header_t header;
+
+  esp_partition_read(app_size_partition, 0, &header, sizeof(header));
+  if (header.magic != ESP_IMAGE_HEADER_MAGIC) {
+    ESP_LOGE(TAG, "KEIN VALIDER HEADER");
+    return 0;
+  }
+
+  u_int32_t data_len = sizeof(header);
+
+  for (int i = 0; i < header.segment_count; i++) {
+    esp_image_segment_header_t segment_header;
+    esp_partition_read(app_size_partition, data_len, &segment_header,
+                       sizeof(segment_header));
+    ESP_LOGI(TAG, "SEGMENT %d Address %d, Segment DataLen %d", i,
+             segment_header.load_addr, segment_header.data_len);
+    data_len += segment_header.data_len + sizeof(segment_header);
+  }
+  return data_len;
+}
+
 void ota_task(void *pvParameter) {
   ESP_LOGI(TAG, "ota_task started");
   ota_task_queue_message_t msg;
diff --git a/main/ota_update.h b/main/ota_update.h
index 0979909..47295cd 100644
--- a/main/ota_update.h
+++ b/main/ota_update.h
@@ -5,6 +5,7 @@
 #include <stdint.h>
 #include <sys/types.h>
 #include "esp_now.h"
+#include "esp_partition.h"
 #include "message_structs.h"
 
 #define UPDATE_BUFFER_SIZE 4096
@@ -44,6 +45,8 @@ enum OTA_UPDATE_STATES {
 
 };
 
+u_int32_t get_app_size(const esp_partition_t *app_size_partition);
+
 int prepare_ota_update();
 esp_err_t write_ota_update(uint32_t write_len, const uint8_t *payload);
 esp_err_t end_ota_update();