diff --git a/src/target/common/emu/fltk.cpp b/src/target/common/emu/fltk.cpp
index 974049e5b3..75bd48a593 100755
--- a/src/target/common/emu/fltk.cpp
+++ b/src/target/common/emu/fltk.cpp
@@ -665,8 +665,42 @@ void PWR_Sleep() {
 void LCD_ForceUpdate() {
     if (changed) {
         changed = false;
+#ifdef BUILDTYPE_DEV
+        for (int x = 0; x < LCD_WIDTH; x++)
+            for (int y = 0; y < LCD_HEIGHT; y++) {
+                switch(gui.pixel_tracking[x][y]) {
+                    case 0:
+                    case 1:
+                        break;
+
+                    case 2:
+                        // draw as blue
+                        gui.image[3*(LCD_WIDTH*y+x)] >>= 3;
+                        gui.image[3*(LCD_WIDTH*y+x)+1] >>= 3;
+                        gui.image[3*(LCD_WIDTH*y+x)+2] |= 0xC0;
+
+                        break;
+
+                    case 3:
+                        // draw as green
+                        gui.image[3*(LCD_WIDTH*y+x)] >>= 3;
+                        gui.image[3*(LCD_WIDTH*y+x)+1] |= 0xC0;
+                        gui.image[3*(LCD_WIDTH*y+x)+2] >>= 3;
+                        break;
+
+                    default:
+                        // draw as red
+                        gui.image[3*(LCD_WIDTH*y+x)] |= 0xC0;
+                        gui.image[3*(LCD_WIDTH*y+x)+1] >>= 3;
+                        gui.image[3*(LCD_WIDTH*y+x)+2] >>= 3;
+                        break;
+                }
+            }
+#endif
         image->redraw();
         Fl::check();
     }
+
+    memset(gui.pixel_tracking, 0, sizeof(gui.pixel_tracking));
 }
 } //extern "C"
diff --git a/src/target/common/emu/fltk.h b/src/target/common/emu/fltk.h
index a42b5c7e8b..906441be25 100755
--- a/src/target/common/emu/fltk.h
+++ b/src/target/common/emu/fltk.h
@@ -60,6 +60,7 @@ struct Gui {
     Fl_Output *final[12];
     u32 last_redraw;
     u8  image[IMAGE_X*IMAGE_Y*3];
+    u8  pixel_tracking[IMAGE_X][IMAGE_Y];
 #if SCREEN_RESIZE
     u8 scaled_img[SCREEN_X*SCREEN_Y*3];
 #endif
diff --git a/src/target/emu_devo8/lcd.c b/src/target/emu_devo8/lcd.c
index 81b3fd240d..e5e0523596 100644
--- a/src/target/emu_devo8/lcd.c
+++ b/src/target/emu_devo8/lcd.c
@@ -26,6 +26,8 @@ void LCD_DrawPixel(unsigned int color)
         gui.image[3*(LCD_WIDTH*gui.y+gui.x)] = r;
         gui.image[3*(LCD_WIDTH*gui.y+gui.x)+1] = g;
         gui.image[3*(LCD_WIDTH*gui.y+gui.x)+2] = b;
+
+        gui.pixel_tracking[gui.x][gui.y]++;
 	}
 	// this must be executed to continue drawing in the next row
     gui.x++;