It's not just a web browser, though. It's the sole method to install software, most similar to a package manager on a desktop operating system. On your point, many package managers do have the ability to browse the remote index of the software they can install (e.g. `brew search [X]`, dnf search [X]`). However, the primary purpose of a package manager, including the App Store, is to install and manage software. This is a critical operating system function, made more critical on iOS by the fact that the App Store is the only way to get software.
