The ability to install applications on iOS devices from locations outside the official Apple App Store is generally restricted. This contrasts with other mobile operating systems, where enabling installations from sources other than the official marketplace is a common feature. This functionality allows users to access applications not vetted or distributed through Apple’s established channels.
The restriction on installing applications from unofficial locations on iOS is a core element of Apple’s security model. It provides users a level of protection against malware and ensures a consistent user experience. Historically, enabling this function on iOS devices required jailbreaking, a process that removes many of the operating system’s built-in limitations, but also exposes the device to potential security risks.