What a dot means
In Star Battle a tap cycles a cell through empty, star, and dot. A dot means “this cell is empty.” It is a note you leave for yourself. The rules only care about stars.
You place a dot when you know a cell cannot hold a star — because its row, column, or region already has one, or because it sits next to a star. Dots make the leftover open cells easier to see.
Auto-dot neighbours puts dots on the eight cells around a star after you place it. That is a help, not a rule. You can add or remove dots by hand. A puzzle is solved by the stars, not by the dots.
Play Star Battle. More on the rules and first moves: How to play Star Battle.