Put the blocks at the right position on the screen, and make them the right size.
Extract Block into its own file.
Indicate which blocks are in the current selection.
Add block images.
Remove placeholder image.
Use random colours for the blocks.
Add new icons.
Make image background transparent.
Only allow adjacent runs of the same color.
Ignore any drags that don't start on a block.
Position the grid in the center.
Extract BlockFactory interface.
Rename BlockGrid to GamePhase and introduce an act() method that can indicate game over state.
Add an intro screen.
Make the plus on the intro screen cycle through the colors.
Nits.
Ignore multi-touch events that were causing crashes.
Remove IntroPhase.cycleAction.
Make illegal moves restart the game.
Remove unused Point class.