How TutuApp is being distributed publicly without Apple's app store?

Question

TutuApp for iOS is being distributed to public without the App Store.

I know that Ad Hoc is one way to distribute apps but it is limited to 100 devices.

I know that Enterprise in-house is another way but intended for internal to companys. (Apple can revoke the certificate and the App cannot be installed)

So what is the way used by TutuApp. Is it legal?

How Xcode made the ipa file without Apple Developer account?

Answer 1

They are using Apple Developer Enterprise Program , to distribute Apps without uploading to iTunes store, the program uses to create proprietary apps designed for and distributed exclusively to internal organization's only.

There is instruction to install & trust enterprise developer certificate when you install the app.

After installing the app, you can check the profile in device

Settings -> General -> Profiles & Device Management -> Enterprise App