Tiled is a general purpose tile map editor for all tile-based games, such as RPGs, platformers or Breakout clones.
License: GPL-2.0
Web page: https://www.mapeditor.org/
Source code: https://github.com/mapeditor/tiled/
Become a sponsor: https://github.com/bjorn
Report the bug: https://github.com/mapeditor/tiled/issues