Narrow is a social media marketing tool designed to help users increase their Twitter following by engaging with targeted audiences. The platform allows users to input specific keywords and topics relevant to their niche, and it interacts with Twitter users who are discussing those topics. This interaction leads to more relevant followers, increasing user engagement on the platform. While specific information about Narrow's current offerings and features can be found on their website at http://narrow.io, the core focus of Narrow remains on utilizing keyword targeting to grow and engage Twitter audiences effectively.