Jul 25, 2016

v1.3
- Adopted navigation drawer instead of option menu,
because it is not shown in some cases.
- Suppressed magnifying the game screen in about 10inch+ tablet
of which aspect ratio is the same as the game screen,
to make margin for background image.

v1.2
- Added background images to use available screen space.

v1.1
- Fixed bug illegal aspect ratio in rare case.
- Reduced memory usage.