[mrep]

If it were possible, many more companies would sidestep the app store like how Fortnite did that with the android play store.

The only reason Fortnite used Apple's app store is because Apple has made it practically impossible to side load apps.

[zepto]

Not only is it possible, it’s trivially easy to sideload apps.

What’s difficult is to distribute commercially, or maliciously without going through Apple.