While Apple's mobile operating system has many nice features, it lacks Android's flexibility. In particular, installing apps on iOS feels very restrictive compared to Android's APK system.

Recently, a new way to install unverified apps (i.e. apps not available in the App Store) is now available on iOS. Best of all, apps installed via this method won't be revoked, and the process doesn't require a jailbreak.

The new installation method is called AltServer/AltStore. While AltStore has been out for a while, the latest version 1.3 now supports downloading apps via IPA files stored in the Files app.

In fact, users can now download an IPA file or load an IPA file via iTunes. Once saved to iOS's Files app, AltStore can automatically locate and install the custom app.

The biggest advantage of AltStore is that it does not require a jailbreak, so there is little danger in using this method.

Currently, AltStore can also exploit the application developer permission system to circumvent the possibility of revocation. As a result, AltStore users can now permanently install any app on their iPhone, even those not on the App Store.

Additionally, AltStore uses separate user permissions to install apps (and exploit the system), so revoking an app (when Apple revokes the enterprise license tied to an app, or blacklists it) causes the app to fail to load , application "undoing" occurs.

Of course, there's a downside: users need to refresh installed apps via AltStore every seven days, and can only install up to 10 custom apps at a time.

AltStore is free to download. Additionally, you can read more about installing AltStore/AltServer and how to use it at AltStore.io.