AltServer

AltStore is an iOS sideloading platform that lets users install applications not available through Apple’s official App Store. It presents each app with a generated store page that includes detailed information and permission listings, and it not users when those permissions change. The service supports adding external “sources”—text‑file based catalogs of apps—so users can expand the catalog beyond the curated selection of verified developers.

The companion desktop component, AltServer, runs on macOS (11 or later) and Windows 10 or later and handles the installation process for AltStore on iOS devices. Users launch AltServer to sign and transfer apps to their iPhone or iPad, enabling a straightforward sideloading workflow without requiring a developer account.

AltStore is open source and encourages self‑publishing; developers can create a source file, host it, and have their apps appear automatically in the store. The project targets indie developers and users who want greater freedom to run niche or experimental iOS applications.