As long as you pass Apple's arbitrary rules, you can make your own browser for iOS. Ladybug uses Apple's test suite as an arbitrary measure of completeness.

However, no browser engine has bothered so far because they'd need to upload a separate app to the app store specifically for EU users, and non-EU developers cannot debug the application on a real device so manpower is region-restricted unless you hack around the limitations.

> As long as you pass Apple's arbitrary rules, you can make your own browser for iOS. Ladybug uses Apple's test suite as an arbitrary measure of completeness.

The browser is called Ladybird and it isn’t Apple’s test suite, web-platform-tests is a collective effort all the major players contribute to. Almost two thousand people have contributed to it:

https://github.com/web-platform-tests/wpt/graphs/contributor...

Kind of. But Apple makes it so hard to develop an engine for EU devices, that no browser makers are currently willing to do it.