When downloading applications from somewhere other than the app store, a manual 'Trust' needs to be initiated on the iDevice being used. The steps below will illustrate how to correct this for the Versus app.
1) Navigate to the Versus App Download Page in Safari and tap 'Download Now', and then Install.
2) Versus will download onto your home screen. When you tap the icon you will see the error below:
3) Tap Cancel, then navigate to your iOS devices 'Settings' and then tap on General.
4) Scroll down and tap 'Profiles' then select 'Neurotopia Inc.'
5) Tap Trust "Neurotopia Inc."
6) Tap 'Trust'
You can now exit settings, and proceed to open the Versus app.