Support for 2STP Has Ended

I have recently started a job at Apple.

As a general policy, Apple employees are not permitted to maintain apps in the App Store.
Accordingly, 2STP Authenticator and 2STP Companion were removed from the iOS and Mac App Stores, respectively, as of September 28th, 2017.

The apps will continue working for the foreseeable future, but no further updates are planned.