Which platform does Apple iOS restrict access to?

Apple iOS is designed to run exclusively on Apple’s hardware, which includes devices like the iPhone, iPad, and iPod Touch. This creates a tightly controlled ecosystem where Apple manages both the software and the hardware. As a result, iOS cannot be installed on products made by other manufacturers, which emphasizes Apple's strategy of keeping their operating system within their own product lineup to ensure optimal performance and security.

This exclusivity allows Apple to maintain a high level of integration between hardware and software, leading to a more consistent user experience. Consequently, iOS does not support installation on any devices outside of what Apple produces, establishing it strictly for Apple products.

In contrast, the other options do not accurately reflect the nature of Apple's restrictions. While there are compatibility considerations with other manufacturers in the tech industry, those are not applicable to iOS, as it is limited strictly to Apple's range of devices.