I've been using Simon Tatham's Puzzles for years, but I appreciate this clean, web-based implementation of Battleships. The mobile responsiveness is particularl

I've been using Simon Tatham's Puzzles for years, but I appreciate this clean, web-based implementation of Battleships. The mobile responsiveness is particularly well done. One suggestion: it would be great to have a 'pencil mark' feature for noting potential ship locations, similar to how Sudoku puzzles handle candidates.