Banked!
All the lines
Step through Dad's line. The engine shows its three best moves.
Engine's top 3
Settings
Dad's book
The key
The two knobs
Add lines: paste a PGN (variations become lines) or a move list
Red-pen review
Reviewing
Tap a move to see the position before it; the gold arrow is the move. Enter jumps to the next reason. Tick "new chunk" where a chunk should start; a chunk is 1 to 4 moves. Moves cannot change on an id: delete the line and add it again.
White lines
Black lines