Finally found what was eating all the RAM :D

Re-enabled the tone key selector in Soundboard
Soundboard now uses OutputStream, like Replay
Constexpr'd a bunch of consts which were going to BSS section
Exiting an app now goes back to main menu
Cleaned up Message array

firmware/tools/world_map.py

@@ -0,0 +1,48 @@
+#!/usr/bin/env python
+
+# Copyright (C) 2017 Furrtek
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+#
+
+from __future__ import print_function
+import sys
+import struct
+from PIL import Image
+
+outfile = open('../../sdcard/world_map.bin', 'wb')
+
+im = Image.open("../../sdcard/world_map.jpg")
+pix = im.load()
+
+outfile.write(struct.pack('H', im.size[0]))
+outfile.write(struct.pack('H', im.size[1]))
+
+for y in range (0, im.size[1]):
+	line = ''
+	for x in range (0, im.size[0]):
+		# RRRRRGGGGGGBBBBB
+		#pixel_lcd = (pix[x, y][0] >> 3) << 11
+		#pixel_lcd |= (pix[x, y][1] >> 2) << 5
+		#pixel_lcd |= (pix[x, y][2] >> 3)
+		#         RRRGGGBB to
+		# RRR00GGG000BB000
+		pixel_lcd = (pix[x, y][0] >> 5) << 5
+		pixel_lcd |= (pix[x, y][1] >> 5) << 2
+		pixel_lcd |= (pix[x, y][2] >> 6)
+		line += struct.pack('B', pixel_lcd)
+	outfile.write(line)
+	print(str(y) + '/' + str(im.size[1]) + '\r', end="")