No.
The difference is Apple only allows Enterprise apps to load from a private server. My work has a few.
This is why Niantic uses TestFlight to Beta test ( Ingress, Pokemon GO, Ingress Prime ). TestFlight is basically an Enterprise app and the beta apps are payloads.
Android will allow unverified code, think .exe files in windows ( use these at your own risk ), so several APK mirror sites exist. As soon as a version of the app is available to 5% of all Android users, someone uploads it to an APK mirror site. Downloading from an APK mirror site is basically half way between Beta and live server. If there is a bug, it will actually effect your live server account and you will have to wait for Devs to fix it. Everyone else on the old version is unaffected.