diff --git a/src/calc.c b/src/calc.c
index c73d932..20bccff 100644
--- a/src/calc.c
+++ b/src/calc.c
@@ -213,14 +213,13 @@ static void add_token()
 // Calculate result, display it and reset
 static void calculate()
 {
-    char temp[RESULT_LENGTH + 2] = "";
-
     trim(excess_chars);
     excess_chars = 0;
     Object obj = parseEval(displayed_code, &env);
     updateText();
 
-    stringNObj(temp, &obj, RESULT_LENGTH);
+    size_t length;
+    char* temp = stringObj(&obj, &length);
     if (obj.type == TYPE_ERROR) {
         text_layer_set_font(s_result_text_layer,
                             fonts_get_system_font(FONT_KEY_GOTHIC_14_BOLD));
@@ -229,6 +228,7 @@ static void calculate()
                             fonts_get_system_font(FONT_KEY_GOTHIC_18_BOLD));
     }
     snprintf(result_text, RESULT_LENGTH, RESULT_PREFIX "%s", temp);
+    free(temp);
     text_layer_set_text(s_result_text_layer, result_text);
 }
 
@@ -470,7 +470,9 @@ static void custom_load(Window* window)
 Object add_window(Object obj1, Object _, struct Environment* env)
 {
     printf("ADD_WINDOW\n");
-    stringObj(header, &obj1);
+    size_t length;
+    char* temp = stringObj(&obj1, &length);
+    sprintf(header, "%s", temp);
 
     if (!s_custom_window) {
         s_custom_window = window_create();