BlockBot v1.2

Plays Block Blast! for you on your Windows PC. It watches the screen and drags the pieces with the mouse.

Install Google Play Games for PC: play.google.com/googleplaygames, sign in.
In it, search Block Blast, install, and open it. Start a Classic game.
Open BlockBot.exe. If Windows says "Windows protected your PC", click More info then Run anyway.
Press F8 (or the Start button). Press F8 or Esc again to stop. Pushing the mouse into a screen corner also stops it.

It can't find the game: click Select game area and drag a box around the game.
v1.1: it now looks at the piece while holding it and lines it up before letting go, and moves its own window off the game by itself.
Pieces land in the wrong spot: click Reset drag, then F8 again.
Pieces don't move at all: switch Input to Window messages.
Still stuck: send Tab the file log.txt from %APPDATA%\BlockBot.
Drops miss when it's fast: switch Speed to Normal.
Answer only mode doesn't touch the mouse: press F8 and it shows the best moves (1, 2, 3) in its little window.

Settings and a log are in %APPDATA%\BlockBot.