These are third-party apps (common on Android) that draw a digital line over the game. These range from simple static lines to complex "calculator" tools.
Calculating how a ball will bounce off the rail is much easier with a straight edge. Mini Ruler 8 Ball Pool
Years later, the hall filled with children learning the game. Some practiced with full-sized cues; some started with the Mini Ruler, tapping tentative shots, learning to feel the table. Marco, grown and steady-handed, taught them one rule above all: measure your angle, trust the little touches, and let small things guide large outcomes. The Mini Ruler, still bright orange and polished by many hands, lived a little legend—proof that sometimes the smallest tools teach the greatest lessons. These are third-party apps (common on Android) that