The Tilery窶冱 memory needs vary greatly with the way you use it. Large tiles use more memory than small ones; color uses more than black and white; and every tile needs some of its own.
The Tilery should have about 30K free memory during normal use. That leaves room for times when you have more open applications than usual, and for when you use features that use extra memory temporarily.
The Tilery窶冱 tile menu will show you how much free memory it has. (See Application Tile Menus for details.) If the free memory is more than 30K, you can probably reduce The Tilery窶冱 memory size by the difference. If it窶冱 less, or if you are getting low-memory warnings from The Tilery, you should definitely give The Tilery more memory.
