In order to use any application install from Appvalley, you will need to trust the
enterprise certificate we are currently using.
In order to trust these certificates you need to go to Settings › General ›
Profiles or Profiles and Device Management. Under the Enterprise App
title, you will see a link which say the name on the Untrusted Enterprise Developer.
Tap this link and tap on Trust. You will need to confirm you want to trust the profile,
after doing that apps should now launch.