Snap to Grid
The Snap to Grid option toggles whether or not figures (and their handles) should be aligned to the grid as they are created and modified. To enable/disable this option:
Press on the Settings Button in the Top Toolbar.
Tap on the Snap to Grid on/off slider to enable or disable the option. The slider will appear with a green background when this option is enabled.
The Snap to Grid option will have a green background when enabled or a gray background when disabled.