The purpose of an app store for mobile applications is to provide a centralized platform for users to discover, download, and install software applications tailored for mobile devices. App stores facilitate the distribution of applications developed by various creators while ensuring a certain level of quality control through review processes. They offer features like user reviews, ratings, and categorized listings, making it easier for users to find apps that suit their needs. Moreover, they enable developers to reach a broader audience and monetize their apps effectively.